ETH Price: $2,758.09 (-1.41%)

Transaction Decoder

Block:
22315060 at Apr-21-2025 04:43:35 AM +UTC
Transaction Fee:
0.000091569225 ETH $0.25
Gas Used:
332,979 Gas / 0.275 Gwei

Account State Difference:

  Address   Before After State Difference Code
(quasarbuilder)
45.99955934333405097 Eth45.999560443485678663 Eth0.000001100151627693
0x51Ee6D7d...00c966B03
0.00390419 Eth
Nonce: 0
0.003812620775 Eth
Nonce: 1
0.000091569225

Execution Trace

ETH 0.002378033855794177 SwappableBridge.swapAndBridge( amountIn=1000000000000000, amountOutMin=15640264006079081832, dstChainId=154, to=0x51Ee6D7dfba4D055841F52A7e92014a00c966B03, refundAddress=0x51Ee6D7dfba4D055841F52A7e92014a00c966B03, zroPaymentAddress=0x0000000000000000000000000000000000000000, adapterParams=0x )
  • UniswapV2Router02.STATICCALL( )
  • ETH 0.001 UniswapV2Router02.swapExactETHForTokens( amountOutMin=15640264006079081832, path=[0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, 0xdD69DB25F6D620A7baD3023c5d32761D353D3De9], to=0x0A9f824C05A74F577A536A8A0c673183a872Dff4, deadline=1745210615 ) => ( amounts=[1000000000000000, 473131022333231199259] )
    • UniswapV2Pair.STATICCALL( )
    • ETH 0.001 WETH9.CALL( )
    • WETH9.transfer( dst=0x4B1e9A9dE809CE968c7dFB0e66F91bB7D794f3ED, wad=1000000000000000 ) => ( True )
    • UniswapV2Pair.swap( amount0Out=0, amount1Out=473131022333231199259, to=0x0A9f824C05A74F577A536A8A0c673183a872Dff4, data=0x )
      • OFT.transfer( to=0x0A9f824C05A74F577A536A8A0c673183a872Dff4, amount=473131022333231199259 ) => ( True )
      • WETH9.balanceOf( 0x4B1e9A9dE809CE968c7dFB0e66F91bB7D794f3ED ) => ( 3551683753592612856 )
      • OFT.balanceOf( account=0x4B1e9A9dE809CE968c7dFB0e66F91bB7D794f3ED ) => ( 1684993615164761983562450 )
      • ETH 0.001378033855794177 OFT.sendFrom( _from=0x0A9f824C05A74F577A536A8A0c673183a872Dff4, _dstChainId=154, _toAddress=0x51EE6D7DFBA4D055841F52A7E92014A00C966B03, _amount=473131022333231199259, _refundAddress=0x51Ee6D7dfba4D055841F52A7e92014a00c966B03, _zroPaymentAddress=0x0000000000000000000000000000000000000000, _adapterParams=0x )
        • ETH 0.001378033855794177 Endpoint.send( _dstChainId=154, _destination=0x4F7A67464B5976D7547C860109E4432D50AFB38EDD69DB25F6D620A7BAD3023C5D32761D353D3DE9, _payload=0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000060000000000000000000000000000000000000000000000019A6030E0E75A7741B000000000000000000000000000000000000000000000000000000000000001451EE6D7DFBA4D055841F52A7E92014A00C966B03000000000000000000000000, _refundAddress=0x51Ee6D7dfba4D055841F52A7e92014a00c966B03, _zroPaymentAddress=0x0000000000000000000000000000000000000000, _adapterParams=0x )
          • ETH 0.001378033855794177 UltraLightNodeV2.send( _ua=0xdD69DB25F6D620A7baD3023c5d32761D353D3De9, 62353, _dstChainId=154, _path=0x4F7A67464B5976D7547C860109E4432D50AFB38EDD69DB25F6D620A7BAD3023C5D32761D353D3DE9, _payload=0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000060000000000000000000000000000000000000000000000019A6030E0E75A7741B000000000000000000000000000000000000000000000000000000000000001451EE6D7DFBA4D055841F52A7E92014A00C966B03000000000000000000000000, _refundAddress=0x51Ee6D7dfba4D055841F52A7e92014a00c966B03, _zroPaymentAddress=0x0000000000000000000000000000000000000000, _adapterParams=0x )
            • NonceContract.increment( _chainId=154, _ua=0xdD69DB25F6D620A7baD3023c5d32761D353D3De9, _path=0x4F7A67464B5976D7547C860109E4432D50AFB38EDD69DB25F6D620A7BAD3023C5D32761D353D3DE9 ) => ( 62353 )
              • Endpoint.getSendLibraryAddress( _userApplication=0xdD69DB25F6D620A7baD3023c5d32761D353D3De9 ) => ( sendLibraryAddress=0x4D73AdB72bC3DD368966edD0f0b2148401A178E2 )
              • OptimizedTransparentUpgradeableProxy.5886ea65( )
                • 0xb830a5afcbebb936c30c607a18bbba9f5b0a592f.5886ea65( )
                  • OptimizedTransparentUpgradeableProxy.88a4124c( )
                  • OptimizedTransparentUpgradeableProxy.c5e193cd( )
                    • 0x3eea8d627ab6983fffc7027ee623fd7699343fc1.c5e193cd( )
                      • OptimizedTransparentUpgradeableProxy.7bc3c9ab( )
                      • TreasuryV2.getFees( payInZro=False, relayerFee=607715042125047268073320, oracleFee=971259967 ) => ( 0 )
                        File 1 of 12: SwappableBridge
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.8.0;
                        import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
                        import "@layerzerolabs/solidity-examples/contracts/token/oft/IOFTCore.sol";
                        import "./INativeOFT.sol";
                        contract SwappableBridge {
                            IOFTCore public immutable oft;
                            INativeOFT public immutable nativeOft;
                            IUniswapV2Router02 public immutable uniswapRouter;
                            constructor(address _oft, address _nativeOft, address _uniswapRouter) {
                                require(_oft != address(0), "SwappableBridge: invalid OFT address");
                                require(_nativeOft != address(0), "SwappableBridge: invalid Native OFT address");
                                require(_uniswapRouter != address(0), "SwappableBridge: invalid Uniswap Router address");
                                oft = IOFTCore(_oft);
                                nativeOft = INativeOFT(_nativeOft);
                                uniswapRouter = IUniswapV2Router02(_uniswapRouter);
                            }
                            function swapAndBridge(uint amountIn, uint amountOutMin, uint16 dstChainId, address to, address payable refundAddress, address zroPaymentAddress, bytes calldata adapterParams) external payable {
                                require(to != address(0), "SwappableBridge: invalid to address");
                                require(msg.value >= amountIn, "SwappableBridge: not enough value sent");
                                address[] memory path = new address[](2);
                                path[0] = uniswapRouter.WETH();
                                path[1] = address(oft);
                                uint[] memory amounts = uniswapRouter.swapExactETHForTokens{value: amountIn}(amountOutMin, path, address(this), block.timestamp);
                                oft.sendFrom{value: msg.value - amountIn}(address(this), dstChainId, abi.encodePacked(to), amounts[1], refundAddress, zroPaymentAddress, adapterParams);
                            }
                            function bridge(uint amountIn, uint16 dstChainId, address to, address payable refundAddress, address zroPaymentAddress, bytes calldata adapterParams) external payable {
                                require(to != address(0), "SwappableBridge: invalid to address");
                                require(msg.value >= amountIn, "SwappableBridge: not enough value sent");
                                nativeOft.deposit{value: amountIn}();
                                nativeOft.sendFrom{value: msg.value - amountIn}(address(this), dstChainId, abi.encodePacked(to), amountIn, refundAddress, zroPaymentAddress, adapterParams);
                            }
                        }// SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev Interface of the ERC165 standard, as defined in the
                         * https://eips.ethereum.org/EIPS/eip-165[EIP].
                         *
                         * Implementers can declare support of contract interfaces, which can then be
                         * queried by others ({ERC165Checker}).
                         *
                         * For an implementation, see {ERC165}.
                         */
                        interface IERC165 {
                            /**
                             * @dev Returns true if this contract implements the interface defined by
                             * `interfaceId`. See the corresponding
                             * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
                             * to learn more about how these ids are created.
                             *
                             * This function call must use less than 30 000 gas.
                             */
                            function supportsInterface(bytes4 interfaceId) external view returns (bool);
                        }
                        pragma solidity >=0.6.2;
                        interface IUniswapV2Router01 {
                            function factory() external pure returns (address);
                            function WETH() external pure returns (address);
                            function addLiquidity(
                                address tokenA,
                                address tokenB,
                                uint amountADesired,
                                uint amountBDesired,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountA, uint amountB, uint liquidity);
                            function addLiquidityETH(
                                address token,
                                uint amountTokenDesired,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
                            function removeLiquidity(
                                address tokenA,
                                address tokenB,
                                uint liquidity,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountA, uint amountB);
                            function removeLiquidityETH(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountToken, uint amountETH);
                            function removeLiquidityWithPermit(
                                address tokenA,
                                address tokenB,
                                uint liquidity,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external returns (uint amountA, uint amountB);
                            function removeLiquidityETHWithPermit(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external returns (uint amountToken, uint amountETH);
                            function swapExactTokensForTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external returns (uint[] memory amounts);
                            function swapTokensForExactTokens(
                                uint amountOut,
                                uint amountInMax,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external returns (uint[] memory amounts);
                            function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
                                external
                                payable
                                returns (uint[] memory amounts);
                            function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
                                external
                                returns (uint[] memory amounts);
                            function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
                                external
                                returns (uint[] memory amounts);
                            function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
                                external
                                payable
                                returns (uint[] memory amounts);
                            function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
                            function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
                            function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
                            function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
                            function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
                        }
                        pragma solidity >=0.6.2;
                        import './IUniswapV2Router01.sol';
                        interface IUniswapV2Router02 is IUniswapV2Router01 {
                            function removeLiquidityETHSupportingFeeOnTransferTokens(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountETH);
                            function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external returns (uint amountETH);
                            function swapExactTokensForTokensSupportingFeeOnTransferTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external;
                            function swapExactETHForTokensSupportingFeeOnTransferTokens(
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external payable;
                            function swapExactTokensForETHSupportingFeeOnTransferTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external;
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.5.0;
                        import "@openzeppelin/contracts/utils/introspection/IERC165.sol";
                        /**
                         * @dev Interface of the IOFT core standard
                         */
                        interface IOFTCore is IERC165 {
                            /**
                             * @dev estimate send token `_tokenId` to (`_dstChainId`, `_toAddress`)
                             * _dstChainId - L0 defined chain id to send tokens too
                             * _toAddress - dynamic bytes array which contains the address to whom you are sending tokens to on the dstChain
                             * _amount - amount of the tokens to transfer
                             * _useZro - indicates to use zro to pay L0 fees
                             * _adapterParam - flexible bytes array to indicate messaging adapter services in L0
                             */
                            function estimateSendFee(uint16 _dstChainId, bytes calldata _toAddress, uint _amount, bool _useZro, bytes calldata _adapterParams) external view returns (uint nativeFee, uint zroFee);
                            /**
                             * @dev send `_amount` amount of token to (`_dstChainId`, `_toAddress`) from `_from`
                             * `_from` the owner of token
                             * `_dstChainId` the destination chain identifier
                             * `_toAddress` can be any size depending on the `dstChainId`.
                             * `_amount` the quantity of tokens in wei
                             * `_refundAddress` the address LayerZero refunds if too much message fee is sent
                             * `_zroPaymentAddress` set to address(0x0) if not paying in ZRO (LayerZero Token)
                             * `_adapterParams` is a flexible bytes array to indicate messaging adapter services
                             */
                            function sendFrom(address _from, uint16 _dstChainId, bytes calldata _toAddress, uint _amount, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                            /**
                             * @dev returns the circulating amount of tokens on current chain
                             */
                            function circulatingSupply() external view returns (uint);
                            /**
                             * @dev returns the address of the ERC20 token
                             */
                            function token() external view returns (address);
                            /**
                             * @dev Emitted when `_amount` tokens are moved from the `_sender` to (`_dstChainId`, `_toAddress`)
                             * `_nonce` is the outbound nonce
                             */
                            event SendToChain(uint16 indexed _dstChainId, address indexed _from, bytes _toAddress, uint _amount);
                            /**
                             * @dev Emitted when `_amount` tokens are received from `_srcChainId` into the `_toAddress` on the local chain.
                             * `_nonce` is the inbound nonce.
                             */
                            event ReceiveFromChain(uint16 indexed _srcChainId, address indexed _to, uint _amount);
                            event SetUseCustomAdapterParams(bool _useCustomAdapterParams);
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.8.0;
                        import "@layerzerolabs/solidity-examples/contracts/token/oft/IOFTCore.sol";
                        interface INativeOFT is IOFTCore {
                            function deposit() external payable;
                        }

                        File 2 of 12: UniswapV2Router02
                        pragma solidity =0.6.6;
                        
                        interface IUniswapV2Factory {
                            event PairCreated(address indexed token0, address indexed token1, address pair, uint);
                        
                            function feeTo() external view returns (address);
                            function feeToSetter() external view returns (address);
                        
                            function getPair(address tokenA, address tokenB) external view returns (address pair);
                            function allPairs(uint) external view returns (address pair);
                            function allPairsLength() external view returns (uint);
                        
                            function createPair(address tokenA, address tokenB) external returns (address pair);
                        
                            function setFeeTo(address) external;
                            function setFeeToSetter(address) external;
                        }
                        
                        interface IUniswapV2Pair {
                            event Approval(address indexed owner, address indexed spender, uint value);
                            event Transfer(address indexed from, address indexed to, uint value);
                        
                            function name() external pure returns (string memory);
                            function symbol() external pure returns (string memory);
                            function decimals() external pure returns (uint8);
                            function totalSupply() external view returns (uint);
                            function balanceOf(address owner) external view returns (uint);
                            function allowance(address owner, address spender) external view returns (uint);
                        
                            function approve(address spender, uint value) external returns (bool);
                            function transfer(address to, uint value) external returns (bool);
                            function transferFrom(address from, address to, uint value) external returns (bool);
                        
                            function DOMAIN_SEPARATOR() external view returns (bytes32);
                            function PERMIT_TYPEHASH() external pure returns (bytes32);
                            function nonces(address owner) external view returns (uint);
                        
                            function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                        
                            event Mint(address indexed sender, uint amount0, uint amount1);
                            event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                            event Swap(
                                address indexed sender,
                                uint amount0In,
                                uint amount1In,
                                uint amount0Out,
                                uint amount1Out,
                                address indexed to
                            );
                            event Sync(uint112 reserve0, uint112 reserve1);
                        
                            function MINIMUM_LIQUIDITY() external pure returns (uint);
                            function factory() external view returns (address);
                            function token0() external view returns (address);
                            function token1() external view returns (address);
                            function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
                            function price0CumulativeLast() external view returns (uint);
                            function price1CumulativeLast() external view returns (uint);
                            function kLast() external view returns (uint);
                        
                            function mint(address to) external returns (uint liquidity);
                            function burn(address to) external returns (uint amount0, uint amount1);
                            function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
                            function skim(address to) external;
                            function sync() external;
                        
                            function initialize(address, address) external;
                        }
                        
                        interface IUniswapV2Router01 {
                            function factory() external pure returns (address);
                            function WETH() external pure returns (address);
                        
                            function addLiquidity(
                                address tokenA,
                                address tokenB,
                                uint amountADesired,
                                uint amountBDesired,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountA, uint amountB, uint liquidity);
                            function addLiquidityETH(
                                address token,
                                uint amountTokenDesired,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
                            function removeLiquidity(
                                address tokenA,
                                address tokenB,
                                uint liquidity,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountA, uint amountB);
                            function removeLiquidityETH(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountToken, uint amountETH);
                            function removeLiquidityWithPermit(
                                address tokenA,
                                address tokenB,
                                uint liquidity,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external returns (uint amountA, uint amountB);
                            function removeLiquidityETHWithPermit(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external returns (uint amountToken, uint amountETH);
                            function swapExactTokensForTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external returns (uint[] memory amounts);
                            function swapTokensForExactTokens(
                                uint amountOut,
                                uint amountInMax,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external returns (uint[] memory amounts);
                            function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
                                external
                                payable
                                returns (uint[] memory amounts);
                            function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
                                external
                                returns (uint[] memory amounts);
                            function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
                                external
                                returns (uint[] memory amounts);
                            function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
                                external
                                payable
                                returns (uint[] memory amounts);
                        
                            function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
                            function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
                            function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
                            function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
                            function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
                        }
                        
                        interface IUniswapV2Router02 is IUniswapV2Router01 {
                            function removeLiquidityETHSupportingFeeOnTransferTokens(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) external returns (uint amountETH);
                            function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external returns (uint amountETH);
                        
                            function swapExactTokensForTokensSupportingFeeOnTransferTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external;
                            function swapExactETHForTokensSupportingFeeOnTransferTokens(
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external payable;
                            function swapExactTokensForETHSupportingFeeOnTransferTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external;
                        }
                        
                        interface IERC20 {
                            event Approval(address indexed owner, address indexed spender, uint value);
                            event Transfer(address indexed from, address indexed to, uint value);
                        
                            function name() external view returns (string memory);
                            function symbol() external view returns (string memory);
                            function decimals() external view returns (uint8);
                            function totalSupply() external view returns (uint);
                            function balanceOf(address owner) external view returns (uint);
                            function allowance(address owner, address spender) external view returns (uint);
                        
                            function approve(address spender, uint value) external returns (bool);
                            function transfer(address to, uint value) external returns (bool);
                            function transferFrom(address from, address to, uint value) external returns (bool);
                        }
                        
                        interface IWETH {
                            function deposit() external payable;
                            function transfer(address to, uint value) external returns (bool);
                            function withdraw(uint) external;
                        }
                        
                        contract UniswapV2Router02 is IUniswapV2Router02 {
                            using SafeMath for uint;
                        
                            address public immutable override factory;
                            address public immutable override WETH;
                        
                            modifier ensure(uint deadline) {
                                require(deadline >= block.timestamp, 'UniswapV2Router: EXPIRED');
                                _;
                            }
                        
                            constructor(address _factory, address _WETH) public {
                                factory = _factory;
                                WETH = _WETH;
                            }
                        
                            receive() external payable {
                                assert(msg.sender == WETH); // only accept ETH via fallback from the WETH contract
                            }
                        
                            // **** ADD LIQUIDITY ****
                            function _addLiquidity(
                                address tokenA,
                                address tokenB,
                                uint amountADesired,
                                uint amountBDesired,
                                uint amountAMin,
                                uint amountBMin
                            ) internal virtual returns (uint amountA, uint amountB) {
                                // create the pair if it doesn't exist yet
                                if (IUniswapV2Factory(factory).getPair(tokenA, tokenB) == address(0)) {
                                    IUniswapV2Factory(factory).createPair(tokenA, tokenB);
                                }
                                (uint reserveA, uint reserveB) = UniswapV2Library.getReserves(factory, tokenA, tokenB);
                                if (reserveA == 0 && reserveB == 0) {
                                    (amountA, amountB) = (amountADesired, amountBDesired);
                                } else {
                                    uint amountBOptimal = UniswapV2Library.quote(amountADesired, reserveA, reserveB);
                                    if (amountBOptimal <= amountBDesired) {
                                        require(amountBOptimal >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
                                        (amountA, amountB) = (amountADesired, amountBOptimal);
                                    } else {
                                        uint amountAOptimal = UniswapV2Library.quote(amountBDesired, reserveB, reserveA);
                                        assert(amountAOptimal <= amountADesired);
                                        require(amountAOptimal >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
                                        (amountA, amountB) = (amountAOptimal, amountBDesired);
                                    }
                                }
                            }
                            function addLiquidity(
                                address tokenA,
                                address tokenB,
                                uint amountADesired,
                                uint amountBDesired,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline
                            ) external virtual override ensure(deadline) returns (uint amountA, uint amountB, uint liquidity) {
                                (amountA, amountB) = _addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin);
                                address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
                                TransferHelper.safeTransferFrom(tokenA, msg.sender, pair, amountA);
                                TransferHelper.safeTransferFrom(tokenB, msg.sender, pair, amountB);
                                liquidity = IUniswapV2Pair(pair).mint(to);
                            }
                            function addLiquidityETH(
                                address token,
                                uint amountTokenDesired,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) external virtual override payable ensure(deadline) returns (uint amountToken, uint amountETH, uint liquidity) {
                                (amountToken, amountETH) = _addLiquidity(
                                    token,
                                    WETH,
                                    amountTokenDesired,
                                    msg.value,
                                    amountTokenMin,
                                    amountETHMin
                                );
                                address pair = UniswapV2Library.pairFor(factory, token, WETH);
                                TransferHelper.safeTransferFrom(token, msg.sender, pair, amountToken);
                                IWETH(WETH).deposit{value: amountETH}();
                                assert(IWETH(WETH).transfer(pair, amountETH));
                                liquidity = IUniswapV2Pair(pair).mint(to);
                                // refund dust eth, if any
                                if (msg.value > amountETH) TransferHelper.safeTransferETH(msg.sender, msg.value - amountETH);
                            }
                        
                            // **** REMOVE LIQUIDITY ****
                            function removeLiquidity(
                                address tokenA,
                                address tokenB,
                                uint liquidity,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline
                            ) public virtual override ensure(deadline) returns (uint amountA, uint amountB) {
                                address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
                                IUniswapV2Pair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair
                                (uint amount0, uint amount1) = IUniswapV2Pair(pair).burn(to);
                                (address token0,) = UniswapV2Library.sortTokens(tokenA, tokenB);
                                (amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0);
                                require(amountA >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
                                require(amountB >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
                            }
                            function removeLiquidityETH(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) public virtual override ensure(deadline) returns (uint amountToken, uint amountETH) {
                                (amountToken, amountETH) = removeLiquidity(
                                    token,
                                    WETH,
                                    liquidity,
                                    amountTokenMin,
                                    amountETHMin,
                                    address(this),
                                    deadline
                                );
                                TransferHelper.safeTransfer(token, to, amountToken);
                                IWETH(WETH).withdraw(amountETH);
                                TransferHelper.safeTransferETH(to, amountETH);
                            }
                            function removeLiquidityWithPermit(
                                address tokenA,
                                address tokenB,
                                uint liquidity,
                                uint amountAMin,
                                uint amountBMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external virtual override returns (uint amountA, uint amountB) {
                                address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
                                uint value = approveMax ? uint(-1) : liquidity;
                                IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
                                (amountA, amountB) = removeLiquidity(tokenA, tokenB, liquidity, amountAMin, amountBMin, to, deadline);
                            }
                            function removeLiquidityETHWithPermit(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external virtual override returns (uint amountToken, uint amountETH) {
                                address pair = UniswapV2Library.pairFor(factory, token, WETH);
                                uint value = approveMax ? uint(-1) : liquidity;
                                IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
                                (amountToken, amountETH) = removeLiquidityETH(token, liquidity, amountTokenMin, amountETHMin, to, deadline);
                            }
                        
                            // **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens) ****
                            function removeLiquidityETHSupportingFeeOnTransferTokens(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline
                            ) public virtual override ensure(deadline) returns (uint amountETH) {
                                (, amountETH) = removeLiquidity(
                                    token,
                                    WETH,
                                    liquidity,
                                    amountTokenMin,
                                    amountETHMin,
                                    address(this),
                                    deadline
                                );
                                TransferHelper.safeTransfer(token, to, IERC20(token).balanceOf(address(this)));
                                IWETH(WETH).withdraw(amountETH);
                                TransferHelper.safeTransferETH(to, amountETH);
                            }
                            function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
                                address token,
                                uint liquidity,
                                uint amountTokenMin,
                                uint amountETHMin,
                                address to,
                                uint deadline,
                                bool approveMax, uint8 v, bytes32 r, bytes32 s
                            ) external virtual override returns (uint amountETH) {
                                address pair = UniswapV2Library.pairFor(factory, token, WETH);
                                uint value = approveMax ? uint(-1) : liquidity;
                                IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
                                amountETH = removeLiquidityETHSupportingFeeOnTransferTokens(
                                    token, liquidity, amountTokenMin, amountETHMin, to, deadline
                                );
                            }
                        
                            // **** SWAP ****
                            // requires the initial amount to have already been sent to the first pair
                            function _swap(uint[] memory amounts, address[] memory path, address _to) internal virtual {
                                for (uint i; i < path.length - 1; i++) {
                                    (address input, address output) = (path[i], path[i + 1]);
                                    (address token0,) = UniswapV2Library.sortTokens(input, output);
                                    uint amountOut = amounts[i + 1];
                                    (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOut) : (amountOut, uint(0));
                                    address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
                                    IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output)).swap(
                                        amount0Out, amount1Out, to, new bytes(0)
                                    );
                                }
                            }
                            function swapExactTokensForTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
                                amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
                                require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                                TransferHelper.safeTransferFrom(
                                    path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                                );
                                _swap(amounts, path, to);
                            }
                            function swapTokensForExactTokens(
                                uint amountOut,
                                uint amountInMax,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
                                amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
                                require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
                                TransferHelper.safeTransferFrom(
                                    path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                                );
                                _swap(amounts, path, to);
                            }
                            function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
                                external
                                virtual
                                override
                                payable
                                ensure(deadline)
                                returns (uint[] memory amounts)
                            {
                                require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
                                amounts = UniswapV2Library.getAmountsOut(factory, msg.value, path);
                                require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                                IWETH(WETH).deposit{value: amounts[0]}();
                                assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
                                _swap(amounts, path, to);
                            }
                            function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
                                external
                                virtual
                                override
                                ensure(deadline)
                                returns (uint[] memory amounts)
                            {
                                require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
                                amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
                                require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
                                TransferHelper.safeTransferFrom(
                                    path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                                );
                                _swap(amounts, path, address(this));
                                IWETH(WETH).withdraw(amounts[amounts.length - 1]);
                                TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
                            }
                            function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
                                external
                                virtual
                                override
                                ensure(deadline)
                                returns (uint[] memory amounts)
                            {
                                require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
                                amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
                                require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                                TransferHelper.safeTransferFrom(
                                    path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                                );
                                _swap(amounts, path, address(this));
                                IWETH(WETH).withdraw(amounts[amounts.length - 1]);
                                TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
                            }
                            function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
                                external
                                virtual
                                override
                                payable
                                ensure(deadline)
                                returns (uint[] memory amounts)
                            {
                                require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
                                amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
                                require(amounts[0] <= msg.value, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
                                IWETH(WETH).deposit{value: amounts[0]}();
                                assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
                                _swap(amounts, path, to);
                                // refund dust eth, if any
                                if (msg.value > amounts[0]) TransferHelper.safeTransferETH(msg.sender, msg.value - amounts[0]);
                            }
                        
                            // **** SWAP (supporting fee-on-transfer tokens) ****
                            // requires the initial amount to have already been sent to the first pair
                            function _swapSupportingFeeOnTransferTokens(address[] memory path, address _to) internal virtual {
                                for (uint i; i < path.length - 1; i++) {
                                    (address input, address output) = (path[i], path[i + 1]);
                                    (address token0,) = UniswapV2Library.sortTokens(input, output);
                                    IUniswapV2Pair pair = IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output));
                                    uint amountInput;
                                    uint amountOutput;
                                    { // scope to avoid stack too deep errors
                                    (uint reserve0, uint reserve1,) = pair.getReserves();
                                    (uint reserveInput, uint reserveOutput) = input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
                                    amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
                                    amountOutput = UniswapV2Library.getAmountOut(amountInput, reserveInput, reserveOutput);
                                    }
                                    (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOutput) : (amountOutput, uint(0));
                                    address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
                                    pair.swap(amount0Out, amount1Out, to, new bytes(0));
                                }
                            }
                            function swapExactTokensForTokensSupportingFeeOnTransferTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            ) external virtual override ensure(deadline) {
                                TransferHelper.safeTransferFrom(
                                    path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
                                );
                                uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
                                _swapSupportingFeeOnTransferTokens(path, to);
                                require(
                                    IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
                                    'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
                                );
                            }
                            function swapExactETHForTokensSupportingFeeOnTransferTokens(
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            )
                                external
                                virtual
                                override
                                payable
                                ensure(deadline)
                            {
                                require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
                                uint amountIn = msg.value;
                                IWETH(WETH).deposit{value: amountIn}();
                                assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn));
                                uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
                                _swapSupportingFeeOnTransferTokens(path, to);
                                require(
                                    IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
                                    'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
                                );
                            }
                            function swapExactTokensForETHSupportingFeeOnTransferTokens(
                                uint amountIn,
                                uint amountOutMin,
                                address[] calldata path,
                                address to,
                                uint deadline
                            )
                                external
                                virtual
                                override
                                ensure(deadline)
                            {
                                require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
                                TransferHelper.safeTransferFrom(
                                    path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
                                );
                                _swapSupportingFeeOnTransferTokens(path, address(this));
                                uint amountOut = IERC20(WETH).balanceOf(address(this));
                                require(amountOut >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                                IWETH(WETH).withdraw(amountOut);
                                TransferHelper.safeTransferETH(to, amountOut);
                            }
                        
                            // **** LIBRARY FUNCTIONS ****
                            function quote(uint amountA, uint reserveA, uint reserveB) public pure virtual override returns (uint amountB) {
                                return UniswapV2Library.quote(amountA, reserveA, reserveB);
                            }
                        
                            function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut)
                                public
                                pure
                                virtual
                                override
                                returns (uint amountOut)
                            {
                                return UniswapV2Library.getAmountOut(amountIn, reserveIn, reserveOut);
                            }
                        
                            function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut)
                                public
                                pure
                                virtual
                                override
                                returns (uint amountIn)
                            {
                                return UniswapV2Library.getAmountIn(amountOut, reserveIn, reserveOut);
                            }
                        
                            function getAmountsOut(uint amountIn, address[] memory path)
                                public
                                view
                                virtual
                                override
                                returns (uint[] memory amounts)
                            {
                                return UniswapV2Library.getAmountsOut(factory, amountIn, path);
                            }
                        
                            function getAmountsIn(uint amountOut, address[] memory path)
                                public
                                view
                                virtual
                                override
                                returns (uint[] memory amounts)
                            {
                                return UniswapV2Library.getAmountsIn(factory, amountOut, path);
                            }
                        }
                        
                        // a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
                        
                        library SafeMath {
                            function add(uint x, uint y) internal pure returns (uint z) {
                                require((z = x + y) >= x, 'ds-math-add-overflow');
                            }
                        
                            function sub(uint x, uint y) internal pure returns (uint z) {
                                require((z = x - y) <= x, 'ds-math-sub-underflow');
                            }
                        
                            function mul(uint x, uint y) internal pure returns (uint z) {
                                require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
                            }
                        }
                        
                        library UniswapV2Library {
                            using SafeMath for uint;
                        
                            // returns sorted token addresses, used to handle return values from pairs sorted in this order
                            function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
                                require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
                                (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
                                require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
                            }
                        
                            // calculates the CREATE2 address for a pair without making any external calls
                            function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
                                (address token0, address token1) = sortTokens(tokenA, tokenB);
                                pair = address(uint(keccak256(abi.encodePacked(
                                        hex'ff',
                                        factory,
                                        keccak256(abi.encodePacked(token0, token1)),
                                        hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
                                    ))));
                            }
                        
                            // fetches and sorts the reserves for a pair
                            function getReserves(address factory, address tokenA, address tokenB) internal view returns (uint reserveA, uint reserveB) {
                                (address token0,) = sortTokens(tokenA, tokenB);
                                (uint reserve0, uint reserve1,) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB)).getReserves();
                                (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
                            }
                        
                            // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
                            function quote(uint amountA, uint reserveA, uint reserveB) internal pure returns (uint amountB) {
                                require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT');
                                require(reserveA > 0 && reserveB > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
                                amountB = amountA.mul(reserveB) / reserveA;
                            }
                        
                            // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
                            function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) internal pure returns (uint amountOut) {
                                require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT');
                                require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
                                uint amountInWithFee = amountIn.mul(997);
                                uint numerator = amountInWithFee.mul(reserveOut);
                                uint denominator = reserveIn.mul(1000).add(amountInWithFee);
                                amountOut = numerator / denominator;
                            }
                        
                            // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
                            function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) internal pure returns (uint amountIn) {
                                require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
                                require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
                                uint numerator = reserveIn.mul(amountOut).mul(1000);
                                uint denominator = reserveOut.sub(amountOut).mul(997);
                                amountIn = (numerator / denominator).add(1);
                            }
                        
                            // performs chained getAmountOut calculations on any number of pairs
                            function getAmountsOut(address factory, uint amountIn, address[] memory path) internal view returns (uint[] memory amounts) {
                                require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
                                amounts = new uint[](path.length);
                                amounts[0] = amountIn;
                                for (uint i; i < path.length - 1; i++) {
                                    (uint reserveIn, uint reserveOut) = getReserves(factory, path[i], path[i + 1]);
                                    amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
                                }
                            }
                        
                            // performs chained getAmountIn calculations on any number of pairs
                            function getAmountsIn(address factory, uint amountOut, address[] memory path) internal view returns (uint[] memory amounts) {
                                require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
                                amounts = new uint[](path.length);
                                amounts[amounts.length - 1] = amountOut;
                                for (uint i = path.length - 1; i > 0; i--) {
                                    (uint reserveIn, uint reserveOut) = getReserves(factory, path[i - 1], path[i]);
                                    amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
                                }
                            }
                        }
                        
                        // helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
                        library TransferHelper {
                            function safeApprove(address token, address to, uint value) internal {
                                // bytes4(keccak256(bytes('approve(address,uint256)')));
                                (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
                                require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
                            }
                        
                            function safeTransfer(address token, address to, uint value) internal {
                                // bytes4(keccak256(bytes('transfer(address,uint256)')));
                                (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
                                require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FAILED');
                            }
                        
                            function safeTransferFrom(address token, address from, address to, uint value) internal {
                                // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
                                (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
                                require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FROM_FAILED');
                            }
                        
                            function safeTransferETH(address to, uint value) internal {
                                (bool success,) = to.call{value:value}(new bytes(0));
                                require(success, 'TransferHelper: ETH_TRANSFER_FAILED');
                            }
                        }

                        File 3 of 12: UniswapV2Pair
                        // File: contracts/interfaces/IUniswapV2Pair.sol
                        
                        pragma solidity >=0.5.0;
                        
                        interface IUniswapV2Pair {
                            event Approval(address indexed owner, address indexed spender, uint value);
                            event Transfer(address indexed from, address indexed to, uint value);
                        
                            function name() external pure returns (string memory);
                            function symbol() external pure returns (string memory);
                            function decimals() external pure returns (uint8);
                            function totalSupply() external view returns (uint);
                            function balanceOf(address owner) external view returns (uint);
                            function allowance(address owner, address spender) external view returns (uint);
                        
                            function approve(address spender, uint value) external returns (bool);
                            function transfer(address to, uint value) external returns (bool);
                            function transferFrom(address from, address to, uint value) external returns (bool);
                        
                            function DOMAIN_SEPARATOR() external view returns (bytes32);
                            function PERMIT_TYPEHASH() external pure returns (bytes32);
                            function nonces(address owner) external view returns (uint);
                        
                            function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                        
                            event Mint(address indexed sender, uint amount0, uint amount1);
                            event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                            event Swap(
                                address indexed sender,
                                uint amount0In,
                                uint amount1In,
                                uint amount0Out,
                                uint amount1Out,
                                address indexed to
                            );
                            event Sync(uint112 reserve0, uint112 reserve1);
                        
                            function MINIMUM_LIQUIDITY() external pure returns (uint);
                            function factory() external view returns (address);
                            function token0() external view returns (address);
                            function token1() external view returns (address);
                            function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
                            function price0CumulativeLast() external view returns (uint);
                            function price1CumulativeLast() external view returns (uint);
                            function kLast() external view returns (uint);
                        
                            function mint(address to) external returns (uint liquidity);
                            function burn(address to) external returns (uint amount0, uint amount1);
                            function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
                            function skim(address to) external;
                            function sync() external;
                        
                            function initialize(address, address) external;
                        }
                        
                        // File: contracts/interfaces/IUniswapV2ERC20.sol
                        
                        pragma solidity >=0.5.0;
                        
                        interface IUniswapV2ERC20 {
                            event Approval(address indexed owner, address indexed spender, uint value);
                            event Transfer(address indexed from, address indexed to, uint value);
                        
                            function name() external pure returns (string memory);
                            function symbol() external pure returns (string memory);
                            function decimals() external pure returns (uint8);
                            function totalSupply() external view returns (uint);
                            function balanceOf(address owner) external view returns (uint);
                            function allowance(address owner, address spender) external view returns (uint);
                        
                            function approve(address spender, uint value) external returns (bool);
                            function transfer(address to, uint value) external returns (bool);
                            function transferFrom(address from, address to, uint value) external returns (bool);
                        
                            function DOMAIN_SEPARATOR() external view returns (bytes32);
                            function PERMIT_TYPEHASH() external pure returns (bytes32);
                            function nonces(address owner) external view returns (uint);
                        
                            function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                        }
                        
                        // File: contracts/libraries/SafeMath.sol
                        
                        pragma solidity =0.5.16;
                        
                        // a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
                        
                        library SafeMath {
                            function add(uint x, uint y) internal pure returns (uint z) {
                                require((z = x + y) >= x, 'ds-math-add-overflow');
                            }
                        
                            function sub(uint x, uint y) internal pure returns (uint z) {
                                require((z = x - y) <= x, 'ds-math-sub-underflow');
                            }
                        
                            function mul(uint x, uint y) internal pure returns (uint z) {
                                require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
                            }
                        }
                        
                        // File: contracts/UniswapV2ERC20.sol
                        
                        pragma solidity =0.5.16;
                        
                        
                        
                        contract UniswapV2ERC20 is IUniswapV2ERC20 {
                            using SafeMath for uint;
                        
                            string public constant name = 'Uniswap V2';
                            string public constant symbol = 'UNI-V2';
                            uint8 public constant decimals = 18;
                            uint  public totalSupply;
                            mapping(address => uint) public balanceOf;
                            mapping(address => mapping(address => uint)) public allowance;
                        
                            bytes32 public DOMAIN_SEPARATOR;
                            // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
                            bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
                            mapping(address => uint) public nonces;
                        
                            event Approval(address indexed owner, address indexed spender, uint value);
                            event Transfer(address indexed from, address indexed to, uint value);
                        
                            constructor() public {
                                uint chainId;
                                assembly {
                                    chainId := chainid
                                }
                                DOMAIN_SEPARATOR = keccak256(
                                    abi.encode(
                                        keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
                                        keccak256(bytes(name)),
                                        keccak256(bytes('1')),
                                        chainId,
                                        address(this)
                                    )
                                );
                            }
                        
                            function _mint(address to, uint value) internal {
                                totalSupply = totalSupply.add(value);
                                balanceOf[to] = balanceOf[to].add(value);
                                emit Transfer(address(0), to, value);
                            }
                        
                            function _burn(address from, uint value) internal {
                                balanceOf[from] = balanceOf[from].sub(value);
                                totalSupply = totalSupply.sub(value);
                                emit Transfer(from, address(0), value);
                            }
                        
                            function _approve(address owner, address spender, uint value) private {
                                allowance[owner][spender] = value;
                                emit Approval(owner, spender, value);
                            }
                        
                            function _transfer(address from, address to, uint value) private {
                                balanceOf[from] = balanceOf[from].sub(value);
                                balanceOf[to] = balanceOf[to].add(value);
                                emit Transfer(from, to, value);
                            }
                        
                            function approve(address spender, uint value) external returns (bool) {
                                _approve(msg.sender, spender, value);
                                return true;
                            }
                        
                            function transfer(address to, uint value) external returns (bool) {
                                _transfer(msg.sender, to, value);
                                return true;
                            }
                        
                            function transferFrom(address from, address to, uint value) external returns (bool) {
                                if (allowance[from][msg.sender] != uint(-1)) {
                                    allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
                                }
                                _transfer(from, to, value);
                                return true;
                            }
                        
                            function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
                                require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
                                bytes32 digest = keccak256(
                                    abi.encodePacked(
                                        '\x19\x01',
                                        DOMAIN_SEPARATOR,
                                        keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
                                    )
                                );
                                address recoveredAddress = ecrecover(digest, v, r, s);
                                require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
                                _approve(owner, spender, value);
                            }
                        }
                        
                        // File: contracts/libraries/Math.sol
                        
                        pragma solidity =0.5.16;
                        
                        // a library for performing various math operations
                        
                        library Math {
                            function min(uint x, uint y) internal pure returns (uint z) {
                                z = x < y ? x : y;
                            }
                        
                            // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
                            function sqrt(uint y) internal pure returns (uint z) {
                                if (y > 3) {
                                    z = y;
                                    uint x = y / 2 + 1;
                                    while (x < z) {
                                        z = x;
                                        x = (y / x + x) / 2;
                                    }
                                } else if (y != 0) {
                                    z = 1;
                                }
                            }
                        }
                        
                        // File: contracts/libraries/UQ112x112.sol
                        
                        pragma solidity =0.5.16;
                        
                        // a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))
                        
                        // range: [0, 2**112 - 1]
                        // resolution: 1 / 2**112
                        
                        library UQ112x112 {
                            uint224 constant Q112 = 2**112;
                        
                            // encode a uint112 as a UQ112x112
                            function encode(uint112 y) internal pure returns (uint224 z) {
                                z = uint224(y) * Q112; // never overflows
                            }
                        
                            // divide a UQ112x112 by a uint112, returning a UQ112x112
                            function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
                                z = x / uint224(y);
                            }
                        }
                        
                        // File: contracts/interfaces/IERC20.sol
                        
                        pragma solidity >=0.5.0;
                        
                        interface IERC20 {
                            event Approval(address indexed owner, address indexed spender, uint value);
                            event Transfer(address indexed from, address indexed to, uint value);
                        
                            function name() external view returns (string memory);
                            function symbol() external view returns (string memory);
                            function decimals() external view returns (uint8);
                            function totalSupply() external view returns (uint);
                            function balanceOf(address owner) external view returns (uint);
                            function allowance(address owner, address spender) external view returns (uint);
                        
                            function approve(address spender, uint value) external returns (bool);
                            function transfer(address to, uint value) external returns (bool);
                            function transferFrom(address from, address to, uint value) external returns (bool);
                        }
                        
                        // File: contracts/interfaces/IUniswapV2Factory.sol
                        
                        pragma solidity >=0.5.0;
                        
                        interface IUniswapV2Factory {
                            event PairCreated(address indexed token0, address indexed token1, address pair, uint);
                        
                            function feeTo() external view returns (address);
                            function feeToSetter() external view returns (address);
                        
                            function getPair(address tokenA, address tokenB) external view returns (address pair);
                            function allPairs(uint) external view returns (address pair);
                            function allPairsLength() external view returns (uint);
                        
                            function createPair(address tokenA, address tokenB) external returns (address pair);
                        
                            function setFeeTo(address) external;
                            function setFeeToSetter(address) external;
                        }
                        
                        // File: contracts/interfaces/IUniswapV2Callee.sol
                        
                        pragma solidity >=0.5.0;
                        
                        interface IUniswapV2Callee {
                            function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
                        }
                        
                        // File: contracts/UniswapV2Pair.sol
                        
                        pragma solidity =0.5.16;
                        
                        
                        
                        
                        
                        
                        
                        
                        contract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {
                            using SafeMath  for uint;
                            using UQ112x112 for uint224;
                        
                            uint public constant MINIMUM_LIQUIDITY = 10**3;
                            bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));
                        
                            address public factory;
                            address public token0;
                            address public token1;
                        
                            uint112 private reserve0;           // uses single storage slot, accessible via getReserves
                            uint112 private reserve1;           // uses single storage slot, accessible via getReserves
                            uint32  private blockTimestampLast; // uses single storage slot, accessible via getReserves
                        
                            uint public price0CumulativeLast;
                            uint public price1CumulativeLast;
                            uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event
                        
                            uint private unlocked = 1;
                            modifier lock() {
                                require(unlocked == 1, 'UniswapV2: LOCKED');
                                unlocked = 0;
                                _;
                                unlocked = 1;
                            }
                        
                            function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
                                _reserve0 = reserve0;
                                _reserve1 = reserve1;
                                _blockTimestampLast = blockTimestampLast;
                            }
                        
                            function _safeTransfer(address token, address to, uint value) private {
                                (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
                                require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
                            }
                        
                            event Mint(address indexed sender, uint amount0, uint amount1);
                            event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                            event Swap(
                                address indexed sender,
                                uint amount0In,
                                uint amount1In,
                                uint amount0Out,
                                uint amount1Out,
                                address indexed to
                            );
                            event Sync(uint112 reserve0, uint112 reserve1);
                        
                            constructor() public {
                                factory = msg.sender;
                            }
                        
                            // called once by the factory at time of deployment
                            function initialize(address _token0, address _token1) external {
                                require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
                                token0 = _token0;
                                token1 = _token1;
                            }
                        
                            // update reserves and, on the first call per block, price accumulators
                            function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
                                require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
                                uint32 blockTimestamp = uint32(block.timestamp % 2**32);
                                uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
                                if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
                                    // * never overflows, and + overflow is desired
                                    price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
                                    price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
                                }
                                reserve0 = uint112(balance0);
                                reserve1 = uint112(balance1);
                                blockTimestampLast = blockTimestamp;
                                emit Sync(reserve0, reserve1);
                            }
                        
                            // if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)
                            function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
                                address feeTo = IUniswapV2Factory(factory).feeTo();
                                feeOn = feeTo != address(0);
                                uint _kLast = kLast; // gas savings
                                if (feeOn) {
                                    if (_kLast != 0) {
                                        uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
                                        uint rootKLast = Math.sqrt(_kLast);
                                        if (rootK > rootKLast) {
                                            uint numerator = totalSupply.mul(rootK.sub(rootKLast));
                                            uint denominator = rootK.mul(5).add(rootKLast);
                                            uint liquidity = numerator / denominator;
                                            if (liquidity > 0) _mint(feeTo, liquidity);
                                        }
                                    }
                                } else if (_kLast != 0) {
                                    kLast = 0;
                                }
                            }
                        
                            // this low-level function should be called from a contract which performs important safety checks
                            function mint(address to) external lock returns (uint liquidity) {
                                (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
                                uint balance0 = IERC20(token0).balanceOf(address(this));
                                uint balance1 = IERC20(token1).balanceOf(address(this));
                                uint amount0 = balance0.sub(_reserve0);
                                uint amount1 = balance1.sub(_reserve1);
                        
                                bool feeOn = _mintFee(_reserve0, _reserve1);
                                uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
                                if (_totalSupply == 0) {
                                    liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
                                   _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
                                } else {
                                    liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
                                }
                                require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
                                _mint(to, liquidity);
                        
                                _update(balance0, balance1, _reserve0, _reserve1);
                                if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
                                emit Mint(msg.sender, amount0, amount1);
                            }
                        
                            // this low-level function should be called from a contract which performs important safety checks
                            function burn(address to) external lock returns (uint amount0, uint amount1) {
                                (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
                                address _token0 = token0;                                // gas savings
                                address _token1 = token1;                                // gas savings
                                uint balance0 = IERC20(_token0).balanceOf(address(this));
                                uint balance1 = IERC20(_token1).balanceOf(address(this));
                                uint liquidity = balanceOf[address(this)];
                        
                                bool feeOn = _mintFee(_reserve0, _reserve1);
                                uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
                                amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
                                amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
                                require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
                                _burn(address(this), liquidity);
                                _safeTransfer(_token0, to, amount0);
                                _safeTransfer(_token1, to, amount1);
                                balance0 = IERC20(_token0).balanceOf(address(this));
                                balance1 = IERC20(_token1).balanceOf(address(this));
                        
                                _update(balance0, balance1, _reserve0, _reserve1);
                                if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
                                emit Burn(msg.sender, amount0, amount1, to);
                            }
                        
                            // this low-level function should be called from a contract which performs important safety checks
                            function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
                                require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
                                (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
                                require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');
                        
                                uint balance0;
                                uint balance1;
                                { // scope for _token{0,1}, avoids stack too deep errors
                                address _token0 = token0;
                                address _token1 = token1;
                                require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
                                if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
                                if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
                                if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
                                balance0 = IERC20(_token0).balanceOf(address(this));
                                balance1 = IERC20(_token1).balanceOf(address(this));
                                }
                                uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
                                uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
                                require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
                                { // scope for reserve{0,1}Adjusted, avoids stack too deep errors
                                uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
                                uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
                                require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
                                }
                        
                                _update(balance0, balance1, _reserve0, _reserve1);
                                emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
                            }
                        
                            // force balances to match reserves
                            function skim(address to) external lock {
                                address _token0 = token0; // gas savings
                                address _token1 = token1; // gas savings
                                _safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));
                                _safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));
                            }
                        
                            // force reserves to match balances
                            function sync() external lock {
                                _update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);
                            }
                        }

                        File 4 of 12: WETH9
                        // Copyright (C) 2015, 2016, 2017 Dapphub
                        
                        // This program is free software: you can redistribute it and/or modify
                        // it under the terms of the GNU General Public License as published by
                        // the Free Software Foundation, either version 3 of the License, or
                        // (at your option) any later version.
                        
                        // This program is distributed in the hope that it will be useful,
                        // but WITHOUT ANY WARRANTY; without even the implied warranty of
                        // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                        // GNU General Public License for more details.
                        
                        // You should have received a copy of the GNU General Public License
                        // along with this program.  If not, see <http://www.gnu.org/licenses/>.
                        
                        pragma solidity ^0.4.18;
                        
                        contract WETH9 {
                            string public name     = "Wrapped Ether";
                            string public symbol   = "WETH";
                            uint8  public decimals = 18;
                        
                            event  Approval(address indexed src, address indexed guy, uint wad);
                            event  Transfer(address indexed src, address indexed dst, uint wad);
                            event  Deposit(address indexed dst, uint wad);
                            event  Withdrawal(address indexed src, uint wad);
                        
                            mapping (address => uint)                       public  balanceOf;
                            mapping (address => mapping (address => uint))  public  allowance;
                        
                            function() public payable {
                                deposit();
                            }
                            function deposit() public payable {
                                balanceOf[msg.sender] += msg.value;
                                Deposit(msg.sender, msg.value);
                            }
                            function withdraw(uint wad) public {
                                require(balanceOf[msg.sender] >= wad);
                                balanceOf[msg.sender] -= wad;
                                msg.sender.transfer(wad);
                                Withdrawal(msg.sender, wad);
                            }
                        
                            function totalSupply() public view returns (uint) {
                                return this.balance;
                            }
                        
                            function approve(address guy, uint wad) public returns (bool) {
                                allowance[msg.sender][guy] = wad;
                                Approval(msg.sender, guy, wad);
                                return true;
                            }
                        
                            function transfer(address dst, uint wad) public returns (bool) {
                                return transferFrom(msg.sender, dst, wad);
                            }
                        
                            function transferFrom(address src, address dst, uint wad)
                                public
                                returns (bool)
                            {
                                require(balanceOf[src] >= wad);
                        
                                if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
                                    require(allowance[src][msg.sender] >= wad);
                                    allowance[src][msg.sender] -= wad;
                                }
                        
                                balanceOf[src] -= wad;
                                balanceOf[dst] += wad;
                        
                                Transfer(src, dst, wad);
                        
                                return true;
                            }
                        }
                        
                        
                        /*
                                            GNU GENERAL PUBLIC LICENSE
                                               Version 3, 29 June 2007
                        
                         Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
                         Everyone is permitted to copy and distribute verbatim copies
                         of this license document, but changing it is not allowed.
                        
                                                    Preamble
                        
                          The GNU General Public License is a free, copyleft license for
                        software and other kinds of works.
                        
                          The licenses for most software and other practical works are designed
                        to take away your freedom to share and change the works.  By contrast,
                        the GNU General Public License is intended to guarantee your freedom to
                        share and change all versions of a program--to make sure it remains free
                        software for all its users.  We, the Free Software Foundation, use the
                        GNU General Public License for most of our software; it applies also to
                        any other work released this way by its authors.  You can apply it to
                        your programs, too.
                        
                          When we speak of free software, we are referring to freedom, not
                        price.  Our General Public Licenses are designed to make sure that you
                        have the freedom to distribute copies of free software (and charge for
                        them if you wish), that you receive source code or can get it if you
                        want it, that you can change the software or use pieces of it in new
                        free programs, and that you know you can do these things.
                        
                          To protect your rights, we need to prevent others from denying you
                        these rights or asking you to surrender the rights.  Therefore, you have
                        certain responsibilities if you distribute copies of the software, or if
                        you modify it: responsibilities to respect the freedom of others.
                        
                          For example, if you distribute copies of such a program, whether
                        gratis or for a fee, you must pass on to the recipients the same
                        freedoms that you received.  You must make sure that they, too, receive
                        or can get the source code.  And you must show them these terms so they
                        know their rights.
                        
                          Developers that use the GNU GPL protect your rights with two steps:
                        (1) assert copyright on the software, and (2) offer you this License
                        giving you legal permission to copy, distribute and/or modify it.
                        
                          For the developers' and authors' protection, the GPL clearly explains
                        that there is no warranty for this free software.  For both users' and
                        authors' sake, the GPL requires that modified versions be marked as
                        changed, so that their problems will not be attributed erroneously to
                        authors of previous versions.
                        
                          Some devices are designed to deny users access to install or run
                        modified versions of the software inside them, although the manufacturer
                        can do so.  This is fundamentally incompatible with the aim of
                        protecting users' freedom to change the software.  The systematic
                        pattern of such abuse occurs in the area of products for individuals to
                        use, which is precisely where it is most unacceptable.  Therefore, we
                        have designed this version of the GPL to prohibit the practice for those
                        products.  If such problems arise substantially in other domains, we
                        stand ready to extend this provision to those domains in future versions
                        of the GPL, as needed to protect the freedom of users.
                        
                          Finally, every program is threatened constantly by software patents.
                        States should not allow patents to restrict development and use of
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                        avoid the special danger that patents applied to a free program could
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                          The precise terms and conditions for copying, distribution and
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                                               TERMS AND CONDITIONS
                        
                          0. Definitions.
                        
                          "This License" refers to version 3 of the GNU General Public License.
                        
                          "Copyright" also means copyright-like laws that apply to other kinds of
                        works, such as semiconductor masks.
                        
                          "The Program" refers to any copyrightable work licensed under this
                        License.  Each licensee is addressed as "you".  "Licensees" and
                        "recipients" may be individuals or organizations.
                        
                          To "modify" a work means to copy from or adapt all or part of the work
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                        exact copy.  The resulting work is called a "modified version" of the
                        earlier work or a work "based on" the earlier work.
                        
                          A "covered work" means either the unmodified Program or a work based
                        on the Program.
                        
                          To "propagate" a work means to do anything with it that, without
                        permission, would make you directly or secondarily liable for
                        infringement under applicable copyright law, except executing it on a
                        computer or modifying a private copy.  Propagation includes copying,
                        distribution (with or without modification), making available to the
                        public, and in some countries other activities as well.
                        
                          To "convey" a work means any kind of propagation that enables other
                        parties to make or receive copies.  Mere interaction with a user through
                        a computer network, with no transfer of a copy, is not conveying.
                        
                          An interactive user interface displays "Appropriate Legal Notices"
                        to the extent that it includes a convenient and prominently visible
                        feature that (1) displays an appropriate copyright notice, and (2)
                        tells the user that there is no warranty for the work (except to the
                        extent that warranties are provided), that licensees may convey the
                        work under this License, and how to view a copy of this License.  If
                        the interface presents a list of user commands or options, such as a
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                          1. Source Code.
                        
                          The "source code" for a work means the preferred form of the work
                        for making modifications to it.  "Object code" means any non-source
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                          A "Standard Interface" means an interface that either is an official
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                        interfaces specified for a particular programming language, one that
                        is widely used among developers working in that language.
                        
                          The "System Libraries" of an executable work include anything, other
                        than the work as a whole, that (a) is included in the normal form of
                        packaging a Major Component, but which is not part of that Major
                        Component, and (b) serves only to enable use of the work with that
                        Major Component, or to implement a Standard Interface for which an
                        implementation is available to the public in source code form.  A
                        "Major Component", in this context, means a major essential component
                        (kernel, window system, and so on) of the specific operating system
                        (if any) on which the executable work runs, or a compiler used to
                        produce the work, or an object code interpreter used to run it.
                        
                          The "Corresponding Source" for a work in object code form means all
                        the source code needed to generate, install, and (for an executable
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                        control those activities.  However, it does not include the work's
                        System Libraries, or general-purpose tools or generally available free
                        programs which are used unmodified in performing those activities but
                        which are not part of the work.  For example, Corresponding Source
                        includes interface definition files associated with source files for
                        the work, and the source code for shared libraries and dynamically
                        linked subprograms that the work is specifically designed to require,
                        such as by intimate data communication or control flow between those
                        subprograms and other parts of the work.
                        
                          The Corresponding Source need not include anything that users
                        can regenerate automatically from other parts of the Corresponding
                        Source.
                        
                          The Corresponding Source for a work in source code form is that
                        same work.
                        
                          2. Basic Permissions.
                        
                          All rights granted under this License are granted for the term of
                        copyright on the Program, and are irrevocable provided the stated
                        conditions are met.  This License explicitly affirms your unlimited
                        permission to run the unmodified Program.  The output from running a
                        covered work is covered by this License only if the output, given its
                        content, constitutes a covered work.  This License acknowledges your
                        rights of fair use or other equivalent, as provided by copyright law.
                        
                          You may make, run and propagate covered works that you do not
                        convey, without conditions so long as your license otherwise remains
                        in force.  You may convey covered works to others for the sole purpose
                        of having them make modifications exclusively for you, or provide you
                        with facilities for running those works, provided that you comply with
                        the terms of this License in conveying all material for which you do
                        not control copyright.  Those thus making or running the covered works
                        for you must do so exclusively on your behalf, under your direction
                        and control, on terms that prohibit them from making any copies of
                        your copyrighted material outside their relationship with you.
                        
                          Conveying under any other circumstances is permitted solely under
                        the conditions stated below.  Sublicensing is not allowed; section 10
                        makes it unnecessary.
                        
                          3. Protecting Users' Legal Rights From Anti-Circumvention Law.
                        
                          No covered work shall be deemed part of an effective technological
                        measure under any applicable law fulfilling obligations under article
                        11 of the WIPO copyright treaty adopted on 20 December 1996, or
                        similar laws prohibiting or restricting circumvention of such
                        measures.
                        
                          When you convey a covered work, you waive any legal power to forbid
                        circumvention of technological measures to the extent such circumvention
                        is effected by exercising rights under this License with respect to
                        the covered work, and you disclaim any intention to limit operation or
                        modification of the work as a means of enforcing, against the work's
                        users, your or third parties' legal rights to forbid circumvention of
                        technological measures.
                        
                          4. Conveying Verbatim Copies.
                        
                          You may convey verbatim copies of the Program's source code as you
                        receive it, in any medium, provided that you conspicuously and
                        appropriately publish on each copy an appropriate copyright notice;
                        keep intact all notices stating that this License and any
                        non-permissive terms added in accord with section 7 apply to the code;
                        keep intact all notices of the absence of any warranty; and give all
                        recipients a copy of this License along with the Program.
                        
                          You may charge any price or no price for each copy that you convey,
                        and you may offer support or warranty protection for a fee.
                        
                          5. Conveying Modified Source Versions.
                        
                          You may convey a work based on the Program, or the modifications to
                        produce it from the Program, in the form of source code under the
                        terms of section 4, provided that you also meet all of these conditions:
                        
                            a) The work must carry prominent notices stating that you modified
                            it, and giving a relevant date.
                        
                            b) The work must carry prominent notices stating that it is
                            released under this License and any conditions added under section
                            7.  This requirement modifies the requirement in section 4 to
                            "keep intact all notices".
                        
                            c) You must license the entire work, as a whole, under this
                            License to anyone who comes into possession of a copy.  This
                            License will therefore apply, along with any applicable section 7
                            additional terms, to the whole of the work, and all its parts,
                            regardless of how they are packaged.  This License gives no
                            permission to license the work in any other way, but it does not
                            invalidate such permission if you have separately received it.
                        
                            d) If the work has interactive user interfaces, each must display
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                            interfaces that do not display Appropriate Legal Notices, your
                            work need not make them do so.
                        
                          A compilation of a covered work with other separate and independent
                        works, which are not by their nature extensions of the covered work,
                        and which are not combined with it such as to form a larger program,
                        in or on a volume of a storage or distribution medium, is called an
                        "aggregate" if the compilation and its resulting copyright are not
                        used to limit the access or legal rights of the compilation's users
                        beyond what the individual works permit.  Inclusion of a covered work
                        in an aggregate does not cause this License to apply to the other
                        parts of the aggregate.
                        
                          6. Conveying Non-Source Forms.
                        
                          You may convey a covered work in object code form under the terms
                        of sections 4 and 5, provided that you also convey the
                        machine-readable Corresponding Source under the terms of this License,
                        in one of these ways:
                        
                            a) Convey the object code in, or embodied in, a physical product
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                            customarily used for software interchange.
                        
                            b) Convey the object code in, or embodied in, a physical product
                            (including a physical distribution medium), accompanied by a
                            written offer, valid for at least three years and valid for as
                            long as you offer spare parts or customer support for that product
                            model, to give anyone who possesses the object code either (1) a
                            copy of the Corresponding Source for all the software in the
                            product that is covered by this License, on a durable physical
                            medium customarily used for software interchange, for a price no
                            more than your reasonable cost of physically performing this
                            conveying of source, or (2) access to copy the
                            Corresponding Source from a network server at no charge.
                        
                            c) Convey individual copies of the object code with a copy of the
                            written offer to provide the Corresponding Source.  This
                            alternative is allowed only occasionally and noncommercially, and
                            only if you received the object code with such an offer, in accord
                            with subsection 6b.
                        
                            d) Convey the object code by offering access from a designated
                            place (gratis or for a charge), and offer equivalent access to the
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                            further charge.  You need not require recipients to copy the
                            Corresponding Source along with the object code.  If the place to
                            copy the object code is a network server, the Corresponding Source
                            may be on a different server (operated by you or a third party)
                            that supports equivalent copying facilities, provided you maintain
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                            available for as long as needed to satisfy these requirements.
                        
                            e) Convey the object code using peer-to-peer transmission, provided
                            you inform other peers where the object code and Corresponding
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                            charge under subsection 6d.
                        
                          A separable portion of the object code, whose source code is excluded
                        from the Corresponding Source as a System Library, need not be
                        included in conveying the object code work.
                        
                          A "User Product" is either (1) a "consumer product", which means any
                        tangible personal property which is normally used for personal, family,
                        or household purposes, or (2) anything designed or sold for incorporation
                        into a dwelling.  In determining whether a product is a consumer product,
                        doubtful cases shall be resolved in favor of coverage.  For a particular
                        product received by a particular user, "normally used" refers to a
                        typical or common use of that class of product, regardless of the status
                        of the particular user or of the way in which the particular user
                        actually uses, or expects or is expected to use, the product.  A product
                        is a consumer product regardless of whether the product has substantial
                        commercial, industrial or non-consumer uses, unless such uses represent
                        the only significant mode of use of the product.
                        
                          "Installation Information" for a User Product means any methods,
                        procedures, authorization keys, or other information required to install
                        and execute modified versions of a covered work in that User Product from
                        a modified version of its Corresponding Source.  The information must
                        suffice to ensure that the continued functioning of the modified object
                        code is in no case prevented or interfered with solely because
                        modification has been made.
                        
                          If you convey an object code work under this section in, or with, or
                        specifically for use in, a User Product, and the conveying occurs as
                        part of a transaction in which the right of possession and use of the
                        User Product is transferred to the recipient in perpetuity or for a
                        fixed term (regardless of how the transaction is characterized), the
                        Corresponding Source conveyed under this section must be accompanied
                        by the Installation Information.  But this requirement does not apply
                        if neither you nor any third party retains the ability to install
                        modified object code on the User Product (for example, the work has
                        been installed in ROM).
                        
                          The requirement to provide Installation Information does not include a
                        requirement to continue to provide support service, warranty, or updates
                        for a work that has been modified or installed by the recipient, or for
                        the User Product in which it has been modified or installed.  Access to a
                        network may be denied when the modification itself materially and
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                        protocols for communication across the network.
                        
                          Corresponding Source conveyed, and Installation Information provided,
                        in accord with this section must be in a format that is publicly
                        documented (and with an implementation available to the public in
                        source code form), and must require no special password or key for
                        unpacking, reading or copying.
                        
                          7. Additional Terms.
                        
                          "Additional permissions" are terms that supplement the terms of this
                        License by making exceptions from one or more of its conditions.
                        Additional permissions that are applicable to the entire Program shall
                        be treated as though they were included in this License, to the extent
                        that they are valid under applicable law.  If additional permissions
                        apply only to part of the Program, that part may be used separately
                        under those permissions, but the entire Program remains governed by
                        this License without regard to the additional permissions.
                        
                          When you convey a copy of a covered work, you may at your option
                        remove any additional permissions from that copy, or from any part of
                        it.  (Additional permissions may be written to require their own
                        removal in certain cases when you modify the work.)  You may place
                        additional permissions on material, added by you to a covered work,
                        for which you have or can give appropriate copyright permission.
                        
                          Notwithstanding any other provision of this License, for material you
                        add to a covered work, you may (if authorized by the copyright holders of
                        that material) supplement the terms of this License with terms:
                        
                            a) Disclaiming warranty or limiting liability differently from the
                            terms of sections 15 and 16 of this License; or
                        
                            b) Requiring preservation of specified reasonable legal notices or
                            author attributions in that material or in the Appropriate Legal
                            Notices displayed by works containing it; or
                        
                            c) Prohibiting misrepresentation of the origin of that material, or
                            requiring that modified versions of such material be marked in
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                            d) Limiting the use for publicity purposes of names of licensors or
                            authors of the material; or
                        
                            e) Declining to grant rights under trademark law for use of some
                            trade names, trademarks, or service marks; or
                        
                            f) Requiring indemnification of licensors and authors of that
                            material by anyone who conveys the material (or modified versions of
                            it) with contractual assumptions of liability to the recipient, for
                            any liability that these contractual assumptions directly impose on
                            those licensors and authors.
                        
                          All other non-permissive additional terms are considered "further
                        restrictions" within the meaning of section 10.  If the Program as you
                        received it, or any part of it, contains a notice stating that it is
                        governed by this License along with a term that is a further
                        restriction, you may remove that term.  If a license document contains
                        a further restriction but permits relicensing or conveying under this
                        License, you may add to a covered work material governed by the terms
                        of that license document, provided that the further restriction does
                        not survive such relicensing or conveying.
                        
                          If you add terms to a covered work in accord with this section, you
                        must place, in the relevant source files, a statement of the
                        additional terms that apply to those files, or a notice indicating
                        where to find the applicable terms.
                        
                          Additional terms, permissive or non-permissive, may be stated in the
                        form of a separately written license, or stated as exceptions;
                        the above requirements apply either way.
                        
                          8. Termination.
                        
                          You may not propagate or modify a covered work except as expressly
                        provided under this License.  Any attempt otherwise to propagate or
                        modify it is void, and will automatically terminate your rights under
                        this License (including any patent licenses granted under the third
                        paragraph of section 11).
                        
                          However, if you cease all violation of this License, then your
                        license from a particular copyright holder is reinstated (a)
                        provisionally, unless and until the copyright holder explicitly and
                        finally terminates your license, and (b) permanently, if the copyright
                        holder fails to notify you of the violation by some reasonable means
                        prior to 60 days after the cessation.
                        
                          Moreover, your license from a particular copyright holder is
                        reinstated permanently if the copyright holder notifies you of the
                        violation by some reasonable means, this is the first time you have
                        received notice of violation of this License (for any work) from that
                        copyright holder, and you cure the violation prior to 30 days after
                        your receipt of the notice.
                        
                          Termination of your rights under this section does not terminate the
                        licenses of parties who have received copies or rights from you under
                        this License.  If your rights have been terminated and not permanently
                        reinstated, you do not qualify to receive new licenses for the same
                        material under section 10.
                        
                          9. Acceptance Not Required for Having Copies.
                        
                          You are not required to accept this License in order to receive or
                        run a copy of the Program.  Ancillary propagation of a covered work
                        occurring solely as a consequence of using peer-to-peer transmission
                        to receive a copy likewise does not require acceptance.  However,
                        nothing other than this License grants you permission to propagate or
                        modify any covered work.  These actions infringe copyright if you do
                        not accept this License.  Therefore, by modifying or propagating a
                        covered work, you indicate your acceptance of this License to do so.
                        
                          10. Automatic Licensing of Downstream Recipients.
                        
                          Each time you convey a covered work, the recipient automatically
                        receives a license from the original licensors, to run, modify and
                        propagate that work, subject to this License.  You are not responsible
                        for enforcing compliance by third parties with this License.
                        
                          An "entity transaction" is a transaction transferring control of an
                        organization, or substantially all assets of one, or subdividing an
                        organization, or merging organizations.  If propagation of a covered
                        work results from an entity transaction, each party to that
                        transaction who receives a copy of the work also receives whatever
                        licenses to the work the party's predecessor in interest had or could
                        give under the previous paragraph, plus a right to possession of the
                        Corresponding Source of the work from the predecessor in interest, if
                        the predecessor has it or can get it with reasonable efforts.
                        
                          You may not impose any further restrictions on the exercise of the
                        rights granted or affirmed under this License.  For example, you may
                        not impose a license fee, royalty, or other charge for exercise of
                        rights granted under this License, and you may not initiate litigation
                        (including a cross-claim or counterclaim in a lawsuit) alleging that
                        any patent claim is infringed by making, using, selling, offering for
                        sale, or importing the Program or any portion of it.
                        
                          11. Patents.
                        
                          A "contributor" is a copyright holder who authorizes use under this
                        License of the Program or a work on which the Program is based.  The
                        work thus licensed is called the contributor's "contributor version".
                        
                          A contributor's "essential patent claims" are all patent claims
                        owned or controlled by the contributor, whether already acquired or
                        hereafter acquired, that would be infringed by some manner, permitted
                        by this License, of making, using, or selling its contributor version,
                        but do not include claims that would be infringed only as a
                        consequence of further modification of the contributor version.  For
                        purposes of this definition, "control" includes the right to grant
                        patent sublicenses in a manner consistent with the requirements of
                        this License.
                        
                          Each contributor grants you a non-exclusive, worldwide, royalty-free
                        patent license under the contributor's essential patent claims, to
                        make, use, sell, offer for sale, import and otherwise run, modify and
                        propagate the contents of its contributor version.
                        
                          In the following three paragraphs, a "patent license" is any express
                        agreement or commitment, however denominated, not to enforce a patent
                        (such as an express permission to practice a patent or covenant not to
                        sue for patent infringement).  To "grant" such a patent license to a
                        party means to make such an agreement or commitment not to enforce a
                        patent against the party.
                        
                          If you convey a covered work, knowingly relying on a patent license,
                        and the Corresponding Source of the work is not available for anyone
                        to copy, free of charge and under the terms of this License, through a
                        publicly available network server or other readily accessible means,
                        then you must either (1) cause the Corresponding Source to be so
                        available, or (2) arrange to deprive yourself of the benefit of the
                        patent license for this particular work, or (3) arrange, in a manner
                        consistent with the requirements of this License, to extend the patent
                        license to downstream recipients.  "Knowingly relying" means you have
                        actual knowledge that, but for the patent license, your conveying the
                        covered work in a country, or your recipient's use of the covered work
                        in a country, would infringe one or more identifiable patents in that
                        country that you have reason to believe are valid.
                        
                          If, pursuant to or in connection with a single transaction or
                        arrangement, you convey, or propagate by procuring conveyance of, a
                        covered work, and grant a patent license to some of the parties
                        receiving the covered work authorizing them to use, propagate, modify
                        or convey a specific copy of the covered work, then the patent license
                        you grant is automatically extended to all recipients of the covered
                        work and works based on it.
                        
                          A patent license is "discriminatory" if it does not include within
                        the scope of its coverage, prohibits the exercise of, or is
                        conditioned on the non-exercise of one or more of the rights that are
                        specifically granted under this License.  You may not convey a covered
                        work if you are a party to an arrangement with a third party that is
                        in the business of distributing software, under which you make payment
                        to the third party based on the extent of your activity of conveying
                        the work, and under which the third party grants, to any of the
                        parties who would receive the covered work from you, a discriminatory
                        patent license (a) in connection with copies of the covered work
                        conveyed by you (or copies made from those copies), or (b) primarily
                        for and in connection with specific products or compilations that
                        contain the covered work, unless you entered into that arrangement,
                        or that patent license was granted, prior to 28 March 2007.
                        
                          Nothing in this License shall be construed as excluding or limiting
                        any implied license or other defenses to infringement that may
                        otherwise be available to you under applicable patent law.
                        
                          12. No Surrender of Others' Freedom.
                        
                          If conditions are imposed on you (whether by court order, agreement or
                        otherwise) that contradict the conditions of this License, they do not
                        excuse you from the conditions of this License.  If you cannot convey a
                        covered work so as to satisfy simultaneously your obligations under this
                        License and any other pertinent obligations, then as a consequence you may
                        not convey it at all.  For example, if you agree to terms that obligate you
                        to collect a royalty for further conveying from those to whom you convey
                        the Program, the only way you could satisfy both those terms and this
                        License would be to refrain entirely from conveying the Program.
                        
                          13. Use with the GNU Affero General Public License.
                        
                          Notwithstanding any other provision of this License, you have
                        permission to link or combine any covered work with a work licensed
                        under version 3 of the GNU Affero General Public License into a single
                        combined work, and to convey the resulting work.  The terms of this
                        License will continue to apply to the part which is the covered work,
                        but the special requirements of the GNU Affero General Public License,
                        section 13, concerning interaction through a network will apply to the
                        combination as such.
                        
                          14. Revised Versions of this License.
                        
                          The Free Software Foundation may publish revised and/or new versions of
                        the GNU General Public License from time to time.  Such new versions will
                        be similar in spirit to the present version, but may differ in detail to
                        address new problems or concerns.
                        
                          Each version is given a distinguishing version number.  If the
                        Program specifies that a certain numbered version of the GNU General
                        Public License "or any later version" applies to it, you have the
                        option of following the terms and conditions either of that numbered
                        version or of any later version published by the Free Software
                        Foundation.  If the Program does not specify a version number of the
                        GNU General Public License, you may choose any version ever published
                        by the Free Software Foundation.
                        
                          If the Program specifies that a proxy can decide which future
                        versions of the GNU General Public License can be used, that proxy's
                        public statement of acceptance of a version permanently authorizes you
                        to choose that version for the Program.
                        
                          Later license versions may give you additional or different
                        permissions.  However, no additional obligations are imposed on any
                        author or copyright holder as a result of your choosing to follow a
                        later version.
                        
                          15. Disclaimer of Warranty.
                        
                          THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
                        APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
                        HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
                        OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
                        THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
                        PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
                        IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
                        ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
                        
                          16. Limitation of Liability.
                        
                          IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
                        WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
                        THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
                        GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
                        USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
                        DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
                        PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
                        EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
                        SUCH DAMAGES.
                        
                          17. Interpretation of Sections 15 and 16.
                        
                          If the disclaimer of warranty and limitation of liability provided
                        above cannot be given local legal effect according to their terms,
                        reviewing courts shall apply local law that most closely approximates
                        an absolute waiver of all civil liability in connection with the
                        Program, unless a warranty or assumption of liability accompanies a
                        copy of the Program in return for a fee.
                        
                                             END OF TERMS AND CONDITIONS
                        
                                    How to Apply These Terms to Your New Programs
                        
                          If you develop a new program, and you want it to be of the greatest
                        possible use to the public, the best way to achieve this is to make it
                        free software which everyone can redistribute and change under these terms.
                        
                          To do so, attach the following notices to the program.  It is safest
                        to attach them to the start of each source file to most effectively
                        state the exclusion of warranty; and each file should have at least
                        the "copyright" line and a pointer to where the full notice is found.
                        
                            <one line to give the program's name and a brief idea of what it does.>
                            Copyright (C) <year>  <name of author>
                        
                            This program is free software: you can redistribute it and/or modify
                            it under the terms of the GNU General Public License as published by
                            the Free Software Foundation, either version 3 of the License, or
                            (at your option) any later version.
                        
                            This program is distributed in the hope that it will be useful,
                            but WITHOUT ANY WARRANTY; without even the implied warranty of
                            MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                            GNU General Public License for more details.
                        
                            You should have received a copy of the GNU General Public License
                            along with this program.  If not, see <http://www.gnu.org/licenses/>.
                        
                        Also add information on how to contact you by electronic and paper mail.
                        
                          If the program does terminal interaction, make it output a short
                        notice like this when it starts in an interactive mode:
                        
                            <program>  Copyright (C) <year>  <name of author>
                            This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
                            This is free software, and you are welcome to redistribute it
                            under certain conditions; type `show c' for details.
                        
                        The hypothetical commands `show w' and `show c' should show the appropriate
                        parts of the General Public License.  Of course, your program's commands
                        might be different; for a GUI interface, you would use an "about box".
                        
                          You should also get your employer (if you work as a programmer) or school,
                        if any, to sign a "copyright disclaimer" for the program, if necessary.
                        For more information on this, and how to apply and follow the GNU GPL, see
                        <http://www.gnu.org/licenses/>.
                        
                          The GNU General Public License does not permit incorporating your program
                        into proprietary programs.  If your program is a subroutine library, you
                        may consider it more useful to permit linking proprietary applications with
                        the library.  If this is what you want to do, use the GNU Lesser General
                        Public License instead of this License.  But first, please read
                        <http://www.gnu.org/philosophy/why-not-lgpl.html>.
                        
                        */

                        File 5 of 12: OFT
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.8.0;
                        import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
                        import "@openzeppelin/contracts/utils/introspection/IERC165.sol";
                        import "./IOFT.sol";
                        import "./OFTCore.sol";
                        // override decimal() function is needed
                        contract OFT is OFTCore, ERC20, IOFT {
                            constructor(string memory _name, string memory _symbol, address _lzEndpoint) ERC20(_name, _symbol) OFTCore(_lzEndpoint) {}
                            function supportsInterface(bytes4 interfaceId) public view virtual override(OFTCore, IERC165) returns (bool) {
                                return interfaceId == type(IOFT).interfaceId || interfaceId == type(IERC20).interfaceId || super.supportsInterface(interfaceId);
                            }
                            function token() public view virtual override returns (address) {
                                return address(this);
                            }
                            function circulatingSupply() public view virtual override returns (uint) {
                                return totalSupply();
                            }
                            function _debitFrom(address _from, uint16, bytes memory, uint _amount) internal virtual override returns(uint) {
                                address spender = _msgSender();
                                if (_from != spender) _spendAllowance(_from, spender, _amount);
                                _burn(_from, _amount);
                                return _amount;
                            }
                            function _creditTo(uint16, address _toAddress, uint _amount) internal virtual override returns(uint) {
                                _mint(_toAddress, _amount);
                                return _amount;
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev Provides information about the current execution context, including the
                         * sender of the transaction and its data. While these are generally available
                         * via msg.sender and msg.data, they should not be accessed in such a direct
                         * manner, since when dealing with meta-transactions the account sending and
                         * paying for execution may not be the actual sender (as far as an application
                         * is concerned).
                         *
                         * This contract is only required for intermediate, library-like contracts.
                         */
                        abstract contract Context {
                            function _msgSender() internal view virtual returns (address) {
                                return msg.sender;
                            }
                            function _msgData() internal view virtual returns (bytes calldata) {
                                return msg.data;
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
                        pragma solidity ^0.8.0;
                        import "../utils/Context.sol";
                        /**
                         * @dev Contract module which provides a basic access control mechanism, where
                         * there is an account (an owner) that can be granted exclusive access to
                         * specific functions.
                         *
                         * By default, the owner account will be the one that deploys the contract. This
                         * can later be changed with {transferOwnership}.
                         *
                         * This module is used through inheritance. It will make available the modifier
                         * `onlyOwner`, which can be applied to your functions to restrict their use to
                         * the owner.
                         */
                        abstract contract Ownable is Context {
                            address private _owner;
                            event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                            /**
                             * @dev Initializes the contract setting the deployer as the initial owner.
                             */
                            constructor() {
                                _transferOwnership(_msgSender());
                            }
                            /**
                             * @dev Throws if called by any account other than the owner.
                             */
                            modifier onlyOwner() {
                                _checkOwner();
                                _;
                            }
                            /**
                             * @dev Returns the address of the current owner.
                             */
                            function owner() public view virtual returns (address) {
                                return _owner;
                            }
                            /**
                             * @dev Throws if the sender is not the owner.
                             */
                            function _checkOwner() internal view virtual {
                                require(owner() == _msgSender(), "Ownable: caller is not the owner");
                            }
                            /**
                             * @dev Leaves the contract without owner. It will not be possible to call
                             * `onlyOwner` functions anymore. Can only be called by the current owner.
                             *
                             * NOTE: Renouncing ownership will leave the contract without an owner,
                             * thereby removing any functionality that is only available to the owner.
                             */
                            function renounceOwnership() public virtual onlyOwner {
                                _transferOwnership(address(0));
                            }
                            /**
                             * @dev Transfers ownership of the contract to a new account (`newOwner`).
                             * Can only be called by the current owner.
                             */
                            function transferOwnership(address newOwner) public virtual onlyOwner {
                                require(newOwner != address(0), "Ownable: new owner is the zero address");
                                _transferOwnership(newOwner);
                            }
                            /**
                             * @dev Transfers ownership of the contract to a new account (`newOwner`).
                             * Internal function without access restriction.
                             */
                            function _transferOwnership(address newOwner) internal virtual {
                                address oldOwner = _owner;
                                _owner = newOwner;
                                emit OwnershipTransferred(oldOwner, newOwner);
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.5.0;
                        interface ILayerZeroReceiver {
                            // @notice LayerZero endpoint will invoke this function to deliver the message on the destination
                            // @param _srcChainId - the source endpoint identifier
                            // @param _srcAddress - the source sending contract address from the source chain
                            // @param _nonce - the ordered message nonce
                            // @param _payload - the signed payload is the UA bytes has encoded to be sent
                            function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) external;
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.5.0;
                        interface ILayerZeroUserApplicationConfig {
                            // @notice set the configuration of the LayerZero messaging library of the specified version
                            // @param _version - messaging library version
                            // @param _chainId - the chainId for the pending config change
                            // @param _configType - type of configuration. every messaging library has its own convention.
                            // @param _config - configuration in the bytes. can encode arbitrary content.
                            function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;
                            // @notice set the send() LayerZero messaging library version to _version
                            // @param _version - new messaging library version
                            function setSendVersion(uint16 _version) external;
                            // @notice set the lzReceive() LayerZero messaging library version to _version
                            // @param _version - new messaging library version
                            function setReceiveVersion(uint16 _version) external;
                            // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
                            // @param _srcChainId - the chainId of the source chain
                            // @param _srcAddress - the contract address of the source contract at the source chain
                            function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.5.0;
                        import "./ILayerZeroUserApplicationConfig.sol";
                        interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
                            // @notice send a LayerZero message to the specified address at a LayerZero endpoint.
                            // @param _dstChainId - the destination chain identifier
                            // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
                            // @param _payload - a custom bytes payload to send to the destination contract
                            // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
                            // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
                            // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
                            function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                            // @notice used by the messaging library to publish verified payload
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source contract (as bytes) at the source chain
                            // @param _dstAddress - the address on destination chain
                            // @param _nonce - the unbound message ordering nonce
                            // @param _gasLimit - the gas limit for external contract execution
                            // @param _payload - verified payload to send to the destination contract
                            function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;
                            // @notice get the inboundNonce of a lzApp from a source chain which could be EVM or non-EVM chain
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
                            // @notice get the outboundNonce from this source chain which, consequently, is always an EVM
                            // @param _srcAddress - the source chain contract address
                            function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
                            // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
                            // @param _dstChainId - the destination chain identifier
                            // @param _userApplication - the user app address on this EVM chain
                            // @param _payload - the custom message to send over LayerZero
                            // @param _payInZRO - if false, user app pays the protocol fee in native token
                            // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
                            function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                            // @notice get this Endpoint's immutable source identifier
                            function getChainId() external view returns (uint16);
                            // @notice the interface to retry failed message on this Endpoint destination
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            // @param _payload - the payload to be retried
                            function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;
                            // @notice query if any STORED payload (message blocking) at the endpoint.
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
                            // @notice query if the _libraryAddress is valid for sending msgs.
                            // @param _userApplication - the user app address on this EVM chain
                            function getSendLibraryAddress(address _userApplication) external view returns (address);
                            // @notice query if the _libraryAddress is valid for receiving msgs.
                            // @param _userApplication - the user app address on this EVM chain
                            function getReceiveLibraryAddress(address _userApplication) external view returns (address);
                            // @notice query if the non-reentrancy guard for send() is on
                            // @return true if the guard is on. false otherwise
                            function isSendingPayload() external view returns (bool);
                            // @notice query if the non-reentrancy guard for receive() is on
                            // @return true if the guard is on. false otherwise
                            function isReceivingPayload() external view returns (bool);
                            // @notice get the configuration of the LayerZero messaging library of the specified version
                            // @param _version - messaging library version
                            // @param _chainId - the chainId for the pending config change
                            // @param _userApplication - the contract address of the user application
                            // @param _configType - type of configuration. every messaging library has its own convention.
                            function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                            // @notice get the send() LayerZero messaging library version
                            // @param _userApplication - the contract address of the user application
                            function getSendVersion(address _userApplication) external view returns (uint16);
                            // @notice get the lzReceive() LayerZero messaging library version
                            // @param _userApplication - the contract address of the user application
                            function getReceiveVersion(address _userApplication) external view returns (uint16);
                        }
                        // SPDX-License-Identifier: Unlicense
                        /*
                         * @title Solidity Bytes Arrays Utils
                         * @author Gonçalo Sá <[email protected]>
                         *
                         * @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
                         *      The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
                         */
                        pragma solidity >=0.8.0 <0.9.0;
                        library BytesLib {
                            function concat(
                                bytes memory _preBytes,
                                bytes memory _postBytes
                            )
                            internal
                            pure
                            returns (bytes memory)
                            {
                                bytes memory tempBytes;
                                assembly {
                                // Get a location of some free memory and store it in tempBytes as
                                // Solidity does for memory variables.
                                    tempBytes := mload(0x40)
                                // Store the length of the first bytes array at the beginning of
                                // the memory for tempBytes.
                                    let length := mload(_preBytes)
                                    mstore(tempBytes, length)
                                // Maintain a memory counter for the current write location in the
                                // temp bytes array by adding the 32 bytes for the array length to
                                // the starting location.
                                    let mc := add(tempBytes, 0x20)
                                // Stop copying when the memory counter reaches the length of the
                                // first bytes array.
                                    let end := add(mc, length)
                                    for {
                                    // Initialize a copy counter to the start of the _preBytes data,
                                    // 32 bytes into its memory.
                                        let cc := add(_preBytes, 0x20)
                                    } lt(mc, end) {
                                    // Increase both counters by 32 bytes each iteration.
                                        mc := add(mc, 0x20)
                                        cc := add(cc, 0x20)
                                    } {
                                    // Write the _preBytes data into the tempBytes memory 32 bytes
                                    // at a time.
                                        mstore(mc, mload(cc))
                                    }
                                // Add the length of _postBytes to the current length of tempBytes
                                // and store it as the new length in the first 32 bytes of the
                                // tempBytes memory.
                                    length := mload(_postBytes)
                                    mstore(tempBytes, add(length, mload(tempBytes)))
                                // Move the memory counter back from a multiple of 0x20 to the
                                // actual end of the _preBytes data.
                                    mc := end
                                // Stop copying when the memory counter reaches the new combined
                                // length of the arrays.
                                    end := add(mc, length)
                                    for {
                                        let cc := add(_postBytes, 0x20)
                                    } lt(mc, end) {
                                        mc := add(mc, 0x20)
                                        cc := add(cc, 0x20)
                                    } {
                                        mstore(mc, mload(cc))
                                    }
                                // Update the free-memory pointer by padding our last write location
                                // to 32 bytes: add 31 bytes to the end of tempBytes to move to the
                                // next 32 byte block, then round down to the nearest multiple of
                                // 32. If the sum of the length of the two arrays is zero then add
                                // one before rounding down to leave a blank 32 bytes (the length block with 0).
                                    mstore(0x40, and(
                                    add(add(end, iszero(add(length, mload(_preBytes)))), 31),
                                    not(31) // Round down to the nearest 32 bytes.
                                    ))
                                }
                                return tempBytes;
                            }
                            function concatStorage(bytes storage _preBytes, bytes memory _postBytes) internal {
                                assembly {
                                // Read the first 32 bytes of _preBytes storage, which is the length
                                // of the array. (We don't need to use the offset into the slot
                                // because arrays use the entire slot.)
                                    let fslot := sload(_preBytes.slot)
                                // Arrays of 31 bytes or less have an even value in their slot,
                                // while longer arrays have an odd value. The actual length is
                                // the slot divided by two for odd values, and the lowest order
                                // byte divided by two for even values.
                                // If the slot is even, bitwise and the slot with 255 and divide by
                                // two to get the length. If the slot is odd, bitwise and the slot
                                // with -1 and divide by two.
                                    let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
                                    let mlength := mload(_postBytes)
                                    let newlength := add(slength, mlength)
                                // slength can contain both the length and contents of the array
                                // if length < 32 bytes so let's prepare for that
                                // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                                    switch add(lt(slength, 32), lt(newlength, 32))
                                    case 2 {
                                    // Since the new array still fits in the slot, we just need to
                                    // update the contents of the slot.
                                    // uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_length
                                        sstore(
                                        _preBytes.slot,
                                        // all the modifications to the slot are inside this
                                        // next block
                                        add(
                                        // we can just add to the slot contents because the
                                        // bytes we want to change are the LSBs
                                        fslot,
                                        add(
                                        mul(
                                        div(
                                        // load the bytes from memory
                                        mload(add(_postBytes, 0x20)),
                                        // zero all bytes to the right
                                        exp(0x100, sub(32, mlength))
                                        ),
                                        // and now shift left the number of bytes to
                                        // leave space for the length in the slot
                                        exp(0x100, sub(32, newlength))
                                        ),
                                        // increase length by the double of the memory
                                        // bytes length
                                        mul(mlength, 2)
                                        )
                                        )
                                        )
                                    }
                                    case 1 {
                                    // The stored value fits in the slot, but the combined value
                                    // will exceed it.
                                    // get the keccak hash to get the contents of the array
                                        mstore(0x0, _preBytes.slot)
                                        let sc := add(keccak256(0x0, 0x20), div(slength, 32))
                                    // save new length
                                        sstore(_preBytes.slot, add(mul(newlength, 2), 1))
                                    // The contents of the _postBytes array start 32 bytes into
                                    // the structure. Our first read should obtain the `submod`
                                    // bytes that can fit into the unused space in the last word
                                    // of the stored array. To get this, we read 32 bytes starting
                                    // from `submod`, so the data we read overlaps with the array
                                    // contents by `submod` bytes. Masking the lowest-order
                                    // `submod` bytes allows us to add that value directly to the
                                    // stored value.
                                        let submod := sub(32, slength)
                                        let mc := add(_postBytes, submod)
                                        let end := add(_postBytes, mlength)
                                        let mask := sub(exp(0x100, submod), 1)
                                        sstore(
                                        sc,
                                        add(
                                        and(
                                        fslot,
                                        0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00
                                        ),
                                        and(mload(mc), mask)
                                        )
                                        )
                                        for {
                                            mc := add(mc, 0x20)
                                            sc := add(sc, 1)
                                        } lt(mc, end) {
                                            sc := add(sc, 1)
                                            mc := add(mc, 0x20)
                                        } {
                                            sstore(sc, mload(mc))
                                        }
                                        mask := exp(0x100, sub(mc, end))
                                        sstore(sc, mul(div(mload(mc), mask), mask))
                                    }
                                    default {
                                    // get the keccak hash to get the contents of the array
                                        mstore(0x0, _preBytes.slot)
                                    // Start copying to the last used word of the stored array.
                                        let sc := add(keccak256(0x0, 0x20), div(slength, 32))
                                    // save new length
                                        sstore(_preBytes.slot, add(mul(newlength, 2), 1))
                                    // Copy over the first `submod` bytes of the new data as in
                                    // case 1 above.
                                        let slengthmod := mod(slength, 32)
                                        let mlengthmod := mod(mlength, 32)
                                        let submod := sub(32, slengthmod)
                                        let mc := add(_postBytes, submod)
                                        let end := add(_postBytes, mlength)
                                        let mask := sub(exp(0x100, submod), 1)
                                        sstore(sc, add(sload(sc), and(mload(mc), mask)))
                                        for {
                                            sc := add(sc, 1)
                                            mc := add(mc, 0x20)
                                        } lt(mc, end) {
                                            sc := add(sc, 1)
                                            mc := add(mc, 0x20)
                                        } {
                                            sstore(sc, mload(mc))
                                        }
                                        mask := exp(0x100, sub(mc, end))
                                        sstore(sc, mul(div(mload(mc), mask), mask))
                                    }
                                }
                            }
                            function slice(
                                bytes memory _bytes,
                                uint256 _start,
                                uint256 _length
                            )
                            internal
                            pure
                            returns (bytes memory)
                            {
                                require(_length + 31 >= _length, "slice_overflow");
                                require(_bytes.length >= _start + _length, "slice_outOfBounds");
                                bytes memory tempBytes;
                                assembly {
                                    switch iszero(_length)
                                    case 0 {
                                    // Get a location of some free memory and store it in tempBytes as
                                    // Solidity does for memory variables.
                                        tempBytes := mload(0x40)
                                    // The first word of the slice result is potentially a partial
                                    // word read from the original array. To read it, we calculate
                                    // the length of that partial word and start copying that many
                                    // bytes into the array. The first word we copy will start with
                                    // data we don't care about, but the last `lengthmod` bytes will
                                    // land at the beginning of the contents of the new array. When
                                    // we're done copying, we overwrite the full first word with
                                    // the actual length of the slice.
                                        let lengthmod := and(_length, 31)
                                    // The multiplication in the next line is necessary
                                    // because when slicing multiples of 32 bytes (lengthmod == 0)
                                    // the following copy loop was copying the origin's length
                                    // and then ending prematurely not copying everything it should.
                                        let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                                        let end := add(mc, _length)
                                        for {
                                        // The multiplication in the next line has the same exact purpose
                                        // as the one above.
                                            let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                                        } lt(mc, end) {
                                            mc := add(mc, 0x20)
                                            cc := add(cc, 0x20)
                                        } {
                                            mstore(mc, mload(cc))
                                        }
                                        mstore(tempBytes, _length)
                                    //update free-memory pointer
                                    //allocating the array padded to 32 bytes like the compiler does now
                                        mstore(0x40, and(add(mc, 31), not(31)))
                                    }
                                    //if we want a zero-length slice let's just return a zero-length array
                                    default {
                                        tempBytes := mload(0x40)
                                    //zero out the 32 bytes slice we are about to return
                                    //we need to do it because Solidity does not garbage collect
                                        mstore(tempBytes, 0)
                                        mstore(0x40, add(tempBytes, 0x20))
                                    }
                                }
                                return tempBytes;
                            }
                            function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
                                require(_bytes.length >= _start + 20, "toAddress_outOfBounds");
                                address tempAddress;
                                assembly {
                                    tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
                                }
                                return tempAddress;
                            }
                            function toUint8(bytes memory _bytes, uint256 _start) internal pure returns (uint8) {
                                require(_bytes.length >= _start + 1 , "toUint8_outOfBounds");
                                uint8 tempUint;
                                assembly {
                                    tempUint := mload(add(add(_bytes, 0x1), _start))
                                }
                                return tempUint;
                            }
                            function toUint16(bytes memory _bytes, uint256 _start) internal pure returns (uint16) {
                                require(_bytes.length >= _start + 2, "toUint16_outOfBounds");
                                uint16 tempUint;
                                assembly {
                                    tempUint := mload(add(add(_bytes, 0x2), _start))
                                }
                                return tempUint;
                            }
                            function toUint32(bytes memory _bytes, uint256 _start) internal pure returns (uint32) {
                                require(_bytes.length >= _start + 4, "toUint32_outOfBounds");
                                uint32 tempUint;
                                assembly {
                                    tempUint := mload(add(add(_bytes, 0x4), _start))
                                }
                                return tempUint;
                            }
                            function toUint64(bytes memory _bytes, uint256 _start) internal pure returns (uint64) {
                                require(_bytes.length >= _start + 8, "toUint64_outOfBounds");
                                uint64 tempUint;
                                assembly {
                                    tempUint := mload(add(add(_bytes, 0x8), _start))
                                }
                                return tempUint;
                            }
                            function toUint96(bytes memory _bytes, uint256 _start) internal pure returns (uint96) {
                                require(_bytes.length >= _start + 12, "toUint96_outOfBounds");
                                uint96 tempUint;
                                assembly {
                                    tempUint := mload(add(add(_bytes, 0xc), _start))
                                }
                                return tempUint;
                            }
                            function toUint128(bytes memory _bytes, uint256 _start) internal pure returns (uint128) {
                                require(_bytes.length >= _start + 16, "toUint128_outOfBounds");
                                uint128 tempUint;
                                assembly {
                                    tempUint := mload(add(add(_bytes, 0x10), _start))
                                }
                                return tempUint;
                            }
                            function toUint256(bytes memory _bytes, uint256 _start) internal pure returns (uint256) {
                                require(_bytes.length >= _start + 32, "toUint256_outOfBounds");
                                uint256 tempUint;
                                assembly {
                                    tempUint := mload(add(add(_bytes, 0x20), _start))
                                }
                                return tempUint;
                            }
                            function toBytes32(bytes memory _bytes, uint256 _start) internal pure returns (bytes32) {
                                require(_bytes.length >= _start + 32, "toBytes32_outOfBounds");
                                bytes32 tempBytes32;
                                assembly {
                                    tempBytes32 := mload(add(add(_bytes, 0x20), _start))
                                }
                                return tempBytes32;
                            }
                            function equal(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bool) {
                                bool success = true;
                                assembly {
                                    let length := mload(_preBytes)
                                // if lengths don't match the arrays are not equal
                                    switch eq(length, mload(_postBytes))
                                    case 1 {
                                    // cb is a circuit breaker in the for loop since there's
                                    //  no said feature for inline assembly loops
                                    // cb = 1 - don't breaker
                                    // cb = 0 - break
                                        let cb := 1
                                        let mc := add(_preBytes, 0x20)
                                        let end := add(mc, length)
                                        for {
                                            let cc := add(_postBytes, 0x20)
                                        // the next line is the loop condition:
                                        // while(uint256(mc < end) + cb == 2)
                                        } eq(add(lt(mc, end), cb), 2) {
                                            mc := add(mc, 0x20)
                                            cc := add(cc, 0x20)
                                        } {
                                        // if any of these checks fails then arrays are not equal
                                            if iszero(eq(mload(mc), mload(cc))) {
                                            // unsuccess:
                                                success := 0
                                                cb := 0
                                            }
                                        }
                                    }
                                    default {
                                    // unsuccess:
                                        success := 0
                                    }
                                }
                                return success;
                            }
                            function equalStorage(
                                bytes storage _preBytes,
                                bytes memory _postBytes
                            )
                            internal
                            view
                            returns (bool)
                            {
                                bool success = true;
                                assembly {
                                // we know _preBytes_offset is 0
                                    let fslot := sload(_preBytes.slot)
                                // Decode the length of the stored array like in concatStorage().
                                    let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
                                    let mlength := mload(_postBytes)
                                // if lengths don't match the arrays are not equal
                                    switch eq(slength, mlength)
                                    case 1 {
                                    // slength can contain both the length and contents of the array
                                    // if length < 32 bytes so let's prepare for that
                                    // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                                        if iszero(iszero(slength)) {
                                            switch lt(slength, 32)
                                            case 1 {
                                            // blank the last byte which is the length
                                                fslot := mul(div(fslot, 0x100), 0x100)
                                                if iszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
                                                // unsuccess:
                                                    success := 0
                                                }
                                            }
                                            default {
                                            // cb is a circuit breaker in the for loop since there's
                                            //  no said feature for inline assembly loops
                                            // cb = 1 - don't breaker
                                            // cb = 0 - break
                                                let cb := 1
                                            // get the keccak hash to get the contents of the array
                                                mstore(0x0, _preBytes.slot)
                                                let sc := keccak256(0x0, 0x20)
                                                let mc := add(_postBytes, 0x20)
                                                let end := add(mc, mlength)
                                            // the next line is the loop condition:
                                            // while(uint256(mc < end) + cb == 2)
                                                for {} eq(add(lt(mc, end), cb), 2) {
                                                    sc := add(sc, 1)
                                                    mc := add(mc, 0x20)
                                                } {
                                                    if iszero(eq(sload(sc), mload(mc))) {
                                                    // unsuccess:
                                                        success := 0
                                                        cb := 0
                                                    }
                                                }
                                            }
                                        }
                                    }
                                    default {
                                    // unsuccess:
                                        success := 0
                                    }
                                }
                                return success;
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.8.0;
                        import "@openzeppelin/contracts/access/Ownable.sol";
                        import "../interfaces/ILayerZeroReceiver.sol";
                        import "../interfaces/ILayerZeroUserApplicationConfig.sol";
                        import "../interfaces/ILayerZeroEndpoint.sol";
                        import "../util/BytesLib.sol";
                        /*
                         * a generic LzReceiver implementation
                         */
                        abstract contract LzApp is Ownable, ILayerZeroReceiver, ILayerZeroUserApplicationConfig {
                            using BytesLib for bytes;
                            ILayerZeroEndpoint public immutable lzEndpoint;
                            mapping(uint16 => bytes) public trustedRemoteLookup;
                            mapping(uint16 => mapping(uint16 => uint)) public minDstGasLookup;
                            address public precrime;
                            event SetPrecrime(address precrime);
                            event SetTrustedRemote(uint16 _remoteChainId, bytes _path);
                            event SetTrustedRemoteAddress(uint16 _remoteChainId, bytes _remoteAddress);
                            event SetMinDstGas(uint16 _dstChainId, uint16 _type, uint _minDstGas);
                            constructor(address _endpoint) {
                                lzEndpoint = ILayerZeroEndpoint(_endpoint);
                            }
                            function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public virtual override {
                                // lzReceive must be called by the endpoint for security
                                require(_msgSender() == address(lzEndpoint), "LzApp: invalid endpoint caller");
                                bytes memory trustedRemote = trustedRemoteLookup[_srcChainId];
                                // if will still block the message pathway from (srcChainId, srcAddress). should not receive message from untrusted remote.
                                require(_srcAddress.length == trustedRemote.length && trustedRemote.length > 0 && keccak256(_srcAddress) == keccak256(trustedRemote), "LzApp: invalid source sending contract");
                                _blockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
                            }
                            // abstract function - the default behaviour of LayerZero is blocking. See: NonblockingLzApp if you dont need to enforce ordered messaging
                            function _blockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual;
                            function _lzSend(uint16 _dstChainId, bytes memory _payload, address payable _refundAddress, address _zroPaymentAddress, bytes memory _adapterParams, uint _nativeFee) internal virtual {
                                bytes memory trustedRemote = trustedRemoteLookup[_dstChainId];
                                require(trustedRemote.length != 0, "LzApp: destination chain is not a trusted source");
                                lzEndpoint.send{value: _nativeFee}(_dstChainId, trustedRemote, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
                            }
                            function _checkGasLimit(uint16 _dstChainId, uint16 _type, bytes memory _adapterParams, uint _extraGas) internal view virtual {
                                uint providedGasLimit = _getGasLimit(_adapterParams);
                                uint minGasLimit = minDstGasLookup[_dstChainId][_type] + _extraGas;
                                require(minGasLimit > 0, "LzApp: minGasLimit not set");
                                require(providedGasLimit >= minGasLimit, "LzApp: gas limit is too low");
                            }
                            function _getGasLimit(bytes memory _adapterParams) internal pure virtual returns (uint gasLimit) {
                                require(_adapterParams.length >= 34, "LzApp: invalid adapterParams");
                                assembly {
                                    gasLimit := mload(add(_adapterParams, 34))
                                }
                            }
                            //---------------------------UserApplication config----------------------------------------
                            function getConfig(uint16 _version, uint16 _chainId, address, uint _configType) external view returns (bytes memory) {
                                return lzEndpoint.getConfig(_version, _chainId, address(this), _configType);
                            }
                            // generic config for LayerZero user Application
                            function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external override onlyOwner {
                                lzEndpoint.setConfig(_version, _chainId, _configType, _config);
                            }
                            function setSendVersion(uint16 _version) external override onlyOwner {
                                lzEndpoint.setSendVersion(_version);
                            }
                            function setReceiveVersion(uint16 _version) external override onlyOwner {
                                lzEndpoint.setReceiveVersion(_version);
                            }
                            function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external override onlyOwner {
                                lzEndpoint.forceResumeReceive(_srcChainId, _srcAddress);
                            }
                            // _path = abi.encodePacked(remoteAddress, localAddress)
                            // this function set the trusted path for the cross-chain communication
                            function setTrustedRemote(uint16 _srcChainId, bytes calldata _path) external onlyOwner {
                                trustedRemoteLookup[_srcChainId] = _path;
                                emit SetTrustedRemote(_srcChainId, _path);
                            }
                            function setTrustedRemoteAddress(uint16 _remoteChainId, bytes calldata _remoteAddress) external onlyOwner {
                                trustedRemoteLookup[_remoteChainId] = abi.encodePacked(_remoteAddress, address(this));
                                emit SetTrustedRemoteAddress(_remoteChainId, _remoteAddress);
                            }
                            function getTrustedRemoteAddress(uint16 _remoteChainId) external view returns (bytes memory) {
                                bytes memory path = trustedRemoteLookup[_remoteChainId];
                                require(path.length != 0, "LzApp: no trusted path record");
                                return path.slice(0, path.length - 20); // the last 20 bytes should be address(this)
                            }
                            function setPrecrime(address _precrime) external onlyOwner {
                                precrime = _precrime;
                                emit SetPrecrime(_precrime);
                            }
                            function setMinDstGas(uint16 _dstChainId, uint16 _packetType, uint _minGas) external onlyOwner {
                                require(_minGas > 0, "LzApp: invalid minGas");
                                minDstGasLookup[_dstChainId][_packetType] = _minGas;
                                emit SetMinDstGas(_dstChainId, _packetType, _minGas);
                            }
                            //--------------------------- VIEW FUNCTION ----------------------------------------
                            function isTrustedRemote(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool) {
                                bytes memory trustedSource = trustedRemoteLookup[_srcChainId];
                                return keccak256(trustedSource) == keccak256(_srcAddress);
                            }
                        }
                        // SPDX-License-Identifier: MIT OR Apache-2.0
                        pragma solidity >=0.7.6;
                        library ExcessivelySafeCall {
                            uint256 constant LOW_28_MASK =
                            0x00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
                            /// @notice Use when you _really_ really _really_ don't trust the called
                            /// contract. This prevents the called contract from causing reversion of
                            /// the caller in as many ways as we can.
                            /// @dev The main difference between this and a solidity low-level call is
                            /// that we limit the number of bytes that the callee can cause to be
                            /// copied to caller memory. This prevents stupid things like malicious
                            /// contracts returning 10,000,000 bytes causing a local OOG when copying
                            /// to memory.
                            /// @param _target The address to call
                            /// @param _gas The amount of gas to forward to the remote contract
                            /// @param _maxCopy The maximum number of bytes of returndata to copy
                            /// to memory.
                            /// @param _calldata The data to send to the remote contract
                            /// @return success and returndata, as `.call()`. Returndata is capped to
                            /// `_maxCopy` bytes.
                            function excessivelySafeCall(
                                address _target,
                                uint256 _gas,
                                uint16 _maxCopy,
                                bytes memory _calldata
                            ) internal returns (bool, bytes memory) {
                                // set up for assembly call
                                uint256 _toCopy;
                                bool _success;
                                bytes memory _returnData = new bytes(_maxCopy);
                                // dispatch message to recipient
                                // by assembly calling "handle" function
                                // we call via assembly to avoid memcopying a very large returndata
                                // returned by a malicious contract
                                assembly {
                                    _success := call(
                                    _gas, // gas
                                    _target, // recipient
                                    0, // ether value
                                    add(_calldata, 0x20), // inloc
                                    mload(_calldata), // inlen
                                    0, // outloc
                                    0 // outlen
                                    )
                                // limit our copy to 256 bytes
                                    _toCopy := returndatasize()
                                    if gt(_toCopy, _maxCopy) {
                                        _toCopy := _maxCopy
                                    }
                                // Store the length of the copied bytes
                                    mstore(_returnData, _toCopy)
                                // copy the bytes from returndata[0:_toCopy]
                                    returndatacopy(add(_returnData, 0x20), 0, _toCopy)
                                }
                                return (_success, _returnData);
                            }
                            /// @notice Use when you _really_ really _really_ don't trust the called
                            /// contract. This prevents the called contract from causing reversion of
                            /// the caller in as many ways as we can.
                            /// @dev The main difference between this and a solidity low-level call is
                            /// that we limit the number of bytes that the callee can cause to be
                            /// copied to caller memory. This prevents stupid things like malicious
                            /// contracts returning 10,000,000 bytes causing a local OOG when copying
                            /// to memory.
                            /// @param _target The address to call
                            /// @param _gas The amount of gas to forward to the remote contract
                            /// @param _maxCopy The maximum number of bytes of returndata to copy
                            /// to memory.
                            /// @param _calldata The data to send to the remote contract
                            /// @return success and returndata, as `.call()`. Returndata is capped to
                            /// `_maxCopy` bytes.
                            function excessivelySafeStaticCall(
                                address _target,
                                uint256 _gas,
                                uint16 _maxCopy,
                                bytes memory _calldata
                            ) internal view returns (bool, bytes memory) {
                                // set up for assembly call
                                uint256 _toCopy;
                                bool _success;
                                bytes memory _returnData = new bytes(_maxCopy);
                                // dispatch message to recipient
                                // by assembly calling "handle" function
                                // we call via assembly to avoid memcopying a very large returndata
                                // returned by a malicious contract
                                assembly {
                                    _success := staticcall(
                                    _gas, // gas
                                    _target, // recipient
                                    add(_calldata, 0x20), // inloc
                                    mload(_calldata), // inlen
                                    0, // outloc
                                    0 // outlen
                                    )
                                // limit our copy to 256 bytes
                                    _toCopy := returndatasize()
                                    if gt(_toCopy, _maxCopy) {
                                        _toCopy := _maxCopy
                                    }
                                // Store the length of the copied bytes
                                    mstore(_returnData, _toCopy)
                                // copy the bytes from returndata[0:_toCopy]
                                    returndatacopy(add(_returnData, 0x20), 0, _toCopy)
                                }
                                return (_success, _returnData);
                            }
                            /**
                             * @notice Swaps function selectors in encoded contract calls
                             * @dev Allows reuse of encoded calldata for functions with identical
                             * argument types but different names. It simply swaps out the first 4 bytes
                             * for the new selector. This function modifies memory in place, and should
                             * only be used with caution.
                             * @param _newSelector The new 4-byte selector
                             * @param _buf The encoded contract args
                             */
                            function swapSelector(bytes4 _newSelector, bytes memory _buf)
                            internal
                            pure
                            {
                                require(_buf.length >= 4);
                                uint256 _mask = LOW_28_MASK;
                                assembly {
                                // load the first word of
                                    let _word := mload(add(_buf, 0x20))
                                // mask out the top 4 bytes
                                // /x
                                    _word := and(_word, _mask)
                                    _word := or(_newSelector, _word)
                                    mstore(add(_buf, 0x20), _word)
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.8.0;
                        import "./LzApp.sol";
                        import "../util/ExcessivelySafeCall.sol";
                        /*
                         * the default LayerZero messaging behaviour is blocking, i.e. any failed message will block the channel
                         * this abstract class try-catch all fail messages and store locally for future retry. hence, non-blocking
                         * NOTE: if the srcAddress is not configured properly, it will still block the message pathway from (srcChainId, srcAddress)
                         */
                        abstract contract NonblockingLzApp is LzApp {
                            using ExcessivelySafeCall for address;
                            constructor(address _endpoint) LzApp(_endpoint) {}
                            mapping(uint16 => mapping(bytes => mapping(uint64 => bytes32))) public failedMessages;
                            event MessageFailed(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes _payload, bytes _reason);
                            event RetryMessageSuccess(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes32 _payloadHash);
                            // overriding the virtual function in LzReceiver
                            function _blockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual override {
                                (bool success, bytes memory reason) = address(this).excessivelySafeCall(gasleft(), 150, abi.encodeWithSelector(this.nonblockingLzReceive.selector, _srcChainId, _srcAddress, _nonce, _payload));
                                // try-catch all errors/exceptions
                                if (!success) {
                                    _storeFailedMessage(_srcChainId, _srcAddress, _nonce, _payload, reason);
                                }
                            }
                            function _storeFailedMessage(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload, bytes memory _reason) internal virtual {
                                failedMessages[_srcChainId][_srcAddress][_nonce] = keccak256(_payload);
                                emit MessageFailed(_srcChainId, _srcAddress, _nonce, _payload, _reason);
                            }
                            function nonblockingLzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public virtual {
                                // only internal transaction
                                require(_msgSender() == address(this), "NonblockingLzApp: caller must be LzApp");
                                _nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
                            }
                            //@notice override this function
                            function _nonblockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual;
                            function retryMessage(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) public payable virtual {
                                // assert there is message to retry
                                bytes32 payloadHash = failedMessages[_srcChainId][_srcAddress][_nonce];
                                require(payloadHash != bytes32(0), "NonblockingLzApp: no stored message");
                                require(keccak256(_payload) == payloadHash, "NonblockingLzApp: invalid payload");
                                // clear the stored message
                                failedMessages[_srcChainId][_srcAddress][_nonce] = bytes32(0);
                                // execute the message. revert if it fails again
                                _nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
                                emit RetryMessageSuccess(_srcChainId, _srcAddress, _nonce, payloadHash);
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.5.0;
                        import "@openzeppelin/contracts/utils/introspection/IERC165.sol";
                        /**
                         * @dev Interface of the IOFT core standard
                         */
                        interface IOFTCore is IERC165 {
                            /**
                             * @dev estimate send token `_tokenId` to (`_dstChainId`, `_toAddress`)
                             * _dstChainId - L0 defined chain id to send tokens too
                             * _toAddress - dynamic bytes array which contains the address to whom you are sending tokens to on the dstChain
                             * _amount - amount of the tokens to transfer
                             * _useZro - indicates to use zro to pay L0 fees
                             * _adapterParam - flexible bytes array to indicate messaging adapter services in L0
                             */
                            function estimateSendFee(uint16 _dstChainId, bytes calldata _toAddress, uint _amount, bool _useZro, bytes calldata _adapterParams) external view returns (uint nativeFee, uint zroFee);
                            /**
                             * @dev send `_amount` amount of token to (`_dstChainId`, `_toAddress`) from `_from`
                             * `_from` the owner of token
                             * `_dstChainId` the destination chain identifier
                             * `_toAddress` can be any size depending on the `dstChainId`.
                             * `_amount` the quantity of tokens in wei
                             * `_refundAddress` the address LayerZero refunds if too much message fee is sent
                             * `_zroPaymentAddress` set to address(0x0) if not paying in ZRO (LayerZero Token)
                             * `_adapterParams` is a flexible bytes array to indicate messaging adapter services
                             */
                            function sendFrom(address _from, uint16 _dstChainId, bytes calldata _toAddress, uint _amount, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                            /**
                             * @dev returns the circulating amount of tokens on current chain
                             */
                            function circulatingSupply() external view returns (uint);
                            /**
                             * @dev returns the address of the ERC20 token
                             */
                            function token() external view returns (address);
                            /**
                             * @dev Emitted when `_amount` tokens are moved from the `_sender` to (`_dstChainId`, `_toAddress`)
                             * `_nonce` is the outbound nonce
                             */
                            event SendToChain(uint16 indexed _dstChainId, address indexed _from, bytes _toAddress, uint _amount);
                            /**
                             * @dev Emitted when `_amount` tokens are received from `_srcChainId` into the `_toAddress` on the local chain.
                             * `_nonce` is the inbound nonce.
                             */
                            event ReceiveFromChain(uint16 indexed _srcChainId, address indexed _to, uint _amount);
                            event SetUseCustomAdapterParams(bool _useCustomAdapterParams);
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
                        pragma solidity ^0.8.0;
                        import "./IERC165.sol";
                        /**
                         * @dev Implementation of the {IERC165} interface.
                         *
                         * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
                         * for the additional interface id that will be supported. For example:
                         *
                         * ```solidity
                         * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                         *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
                         * }
                         * ```
                         *
                         * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
                         */
                        abstract contract ERC165 is IERC165 {
                            /**
                             * @dev See {IERC165-supportsInterface}.
                             */
                            function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                                return interfaceId == type(IERC165).interfaceId;
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev Interface of the ERC20 standard as defined in the EIP.
                         */
                        interface IERC20 {
                            /**
                             * @dev Emitted when `value` tokens are moved from one account (`from`) to
                             * another (`to`).
                             *
                             * Note that `value` may be zero.
                             */
                            event Transfer(address indexed from, address indexed to, uint256 value);
                            /**
                             * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                             * a call to {approve}. `value` is the new allowance.
                             */
                            event Approval(address indexed owner, address indexed spender, uint256 value);
                            /**
                             * @dev Returns the amount of tokens in existence.
                             */
                            function totalSupply() external view returns (uint256);
                            /**
                             * @dev Returns the amount of tokens owned by `account`.
                             */
                            function balanceOf(address account) external view returns (uint256);
                            /**
                             * @dev Moves `amount` tokens from the caller's account to `to`.
                             *
                             * Returns a boolean value indicating whether the operation succeeded.
                             *
                             * Emits a {Transfer} event.
                             */
                            function transfer(address to, uint256 amount) external returns (bool);
                            /**
                             * @dev Returns the remaining number of tokens that `spender` will be
                             * allowed to spend on behalf of `owner` through {transferFrom}. This is
                             * zero by default.
                             *
                             * This value changes when {approve} or {transferFrom} are called.
                             */
                            function allowance(address owner, address spender) external view returns (uint256);
                            /**
                             * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                             *
                             * Returns a boolean value indicating whether the operation succeeded.
                             *
                             * IMPORTANT: Beware that changing an allowance with this method brings the risk
                             * that someone may use both the old and the new allowance by unfortunate
                             * transaction ordering. One possible solution to mitigate this race
                             * condition is to first reduce the spender's allowance to 0 and set the
                             * desired value afterwards:
                             * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                             *
                             * Emits an {Approval} event.
                             */
                            function approve(address spender, uint256 amount) external returns (bool);
                            /**
                             * @dev Moves `amount` tokens from `from` to `to` using the
                             * allowance mechanism. `amount` is then deducted from the caller's
                             * allowance.
                             *
                             * Returns a boolean value indicating whether the operation succeeded.
                             *
                             * Emits a {Transfer} event.
                             */
                            function transferFrom(
                                address from,
                                address to,
                                uint256 amount
                            ) external returns (bool);
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
                        pragma solidity ^0.8.0;
                        import "../IERC20.sol";
                        /**
                         * @dev Interface for the optional metadata functions from the ERC20 standard.
                         *
                         * _Available since v4.1._
                         */
                        interface IERC20Metadata is IERC20 {
                            /**
                             * @dev Returns the name of the token.
                             */
                            function name() external view returns (string memory);
                            /**
                             * @dev Returns the symbol of the token.
                             */
                            function symbol() external view returns (string memory);
                            /**
                             * @dev Returns the decimals places of the token.
                             */
                            function decimals() external view returns (uint8);
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)
                        pragma solidity ^0.8.0;
                        import "./IERC20.sol";
                        import "./extensions/IERC20Metadata.sol";
                        import "../../utils/Context.sol";
                        /**
                         * @dev Implementation of the {IERC20} interface.
                         *
                         * This implementation is agnostic to the way tokens are created. This means
                         * that a supply mechanism has to be added in a derived contract using {_mint}.
                         * For a generic mechanism see {ERC20PresetMinterPauser}.
                         *
                         * TIP: For a detailed writeup see our guide
                         * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
                         * to implement supply mechanisms].
                         *
                         * We have followed general OpenZeppelin Contracts guidelines: functions revert
                         * instead returning `false` on failure. This behavior is nonetheless
                         * conventional and does not conflict with the expectations of ERC20
                         * applications.
                         *
                         * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
                         * This allows applications to reconstruct the allowance for all accounts just
                         * by listening to said events. Other implementations of the EIP may not emit
                         * these events, as it isn't required by the specification.
                         *
                         * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
                         * functions have been added to mitigate the well-known issues around setting
                         * allowances. See {IERC20-approve}.
                         */
                        contract ERC20 is Context, IERC20, IERC20Metadata {
                            mapping(address => uint256) private _balances;
                            mapping(address => mapping(address => uint256)) private _allowances;
                            uint256 private _totalSupply;
                            string private _name;
                            string private _symbol;
                            /**
                             * @dev Sets the values for {name} and {symbol}.
                             *
                             * The default value of {decimals} is 18. To select a different value for
                             * {decimals} you should overload it.
                             *
                             * All two of these values are immutable: they can only be set once during
                             * construction.
                             */
                            constructor(string memory name_, string memory symbol_) {
                                _name = name_;
                                _symbol = symbol_;
                            }
                            /**
                             * @dev Returns the name of the token.
                             */
                            function name() public view virtual override returns (string memory) {
                                return _name;
                            }
                            /**
                             * @dev Returns the symbol of the token, usually a shorter version of the
                             * name.
                             */
                            function symbol() public view virtual override returns (string memory) {
                                return _symbol;
                            }
                            /**
                             * @dev Returns the number of decimals used to get its user representation.
                             * For example, if `decimals` equals `2`, a balance of `505` tokens should
                             * be displayed to a user as `5.05` (`505 / 10 ** 2`).
                             *
                             * Tokens usually opt for a value of 18, imitating the relationship between
                             * Ether and Wei. This is the value {ERC20} uses, unless this function is
                             * overridden;
                             *
                             * NOTE: This information is only used for _display_ purposes: it in
                             * no way affects any of the arithmetic of the contract, including
                             * {IERC20-balanceOf} and {IERC20-transfer}.
                             */
                            function decimals() public view virtual override returns (uint8) {
                                return 18;
                            }
                            /**
                             * @dev See {IERC20-totalSupply}.
                             */
                            function totalSupply() public view virtual override returns (uint256) {
                                return _totalSupply;
                            }
                            /**
                             * @dev See {IERC20-balanceOf}.
                             */
                            function balanceOf(address account) public view virtual override returns (uint256) {
                                return _balances[account];
                            }
                            /**
                             * @dev See {IERC20-transfer}.
                             *
                             * Requirements:
                             *
                             * - `to` cannot be the zero address.
                             * - the caller must have a balance of at least `amount`.
                             */
                            function transfer(address to, uint256 amount) public virtual override returns (bool) {
                                address owner = _msgSender();
                                _transfer(owner, to, amount);
                                return true;
                            }
                            /**
                             * @dev See {IERC20-allowance}.
                             */
                            function allowance(address owner, address spender) public view virtual override returns (uint256) {
                                return _allowances[owner][spender];
                            }
                            /**
                             * @dev See {IERC20-approve}.
                             *
                             * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
                             * `transferFrom`. This is semantically equivalent to an infinite approval.
                             *
                             * Requirements:
                             *
                             * - `spender` cannot be the zero address.
                             */
                            function approve(address spender, uint256 amount) public virtual override returns (bool) {
                                address owner = _msgSender();
                                _approve(owner, spender, amount);
                                return true;
                            }
                            /**
                             * @dev See {IERC20-transferFrom}.
                             *
                             * Emits an {Approval} event indicating the updated allowance. This is not
                             * required by the EIP. See the note at the beginning of {ERC20}.
                             *
                             * NOTE: Does not update the allowance if the current allowance
                             * is the maximum `uint256`.
                             *
                             * Requirements:
                             *
                             * - `from` and `to` cannot be the zero address.
                             * - `from` must have a balance of at least `amount`.
                             * - the caller must have allowance for ``from``'s tokens of at least
                             * `amount`.
                             */
                            function transferFrom(
                                address from,
                                address to,
                                uint256 amount
                            ) public virtual override returns (bool) {
                                address spender = _msgSender();
                                _spendAllowance(from, spender, amount);
                                _transfer(from, to, amount);
                                return true;
                            }
                            /**
                             * @dev Atomically increases the allowance granted to `spender` by the caller.
                             *
                             * This is an alternative to {approve} that can be used as a mitigation for
                             * problems described in {IERC20-approve}.
                             *
                             * Emits an {Approval} event indicating the updated allowance.
                             *
                             * Requirements:
                             *
                             * - `spender` cannot be the zero address.
                             */
                            function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                                address owner = _msgSender();
                                _approve(owner, spender, allowance(owner, spender) + addedValue);
                                return true;
                            }
                            /**
                             * @dev Atomically decreases the allowance granted to `spender` by the caller.
                             *
                             * This is an alternative to {approve} that can be used as a mitigation for
                             * problems described in {IERC20-approve}.
                             *
                             * Emits an {Approval} event indicating the updated allowance.
                             *
                             * Requirements:
                             *
                             * - `spender` cannot be the zero address.
                             * - `spender` must have allowance for the caller of at least
                             * `subtractedValue`.
                             */
                            function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                                address owner = _msgSender();
                                uint256 currentAllowance = allowance(owner, spender);
                                require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
                                unchecked {
                                    _approve(owner, spender, currentAllowance - subtractedValue);
                                }
                                return true;
                            }
                            /**
                             * @dev Moves `amount` of tokens from `from` to `to`.
                             *
                             * This internal function is equivalent to {transfer}, and can be used to
                             * e.g. implement automatic token fees, slashing mechanisms, etc.
                             *
                             * Emits a {Transfer} event.
                             *
                             * Requirements:
                             *
                             * - `from` cannot be the zero address.
                             * - `to` cannot be the zero address.
                             * - `from` must have a balance of at least `amount`.
                             */
                            function _transfer(
                                address from,
                                address to,
                                uint256 amount
                            ) internal virtual {
                                require(from != address(0), "ERC20: transfer from the zero address");
                                require(to != address(0), "ERC20: transfer to the zero address");
                                _beforeTokenTransfer(from, to, amount);
                                uint256 fromBalance = _balances[from];
                                require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
                                unchecked {
                                    _balances[from] = fromBalance - amount;
                                    // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
                                    // decrementing then incrementing.
                                    _balances[to] += amount;
                                }
                                emit Transfer(from, to, amount);
                                _afterTokenTransfer(from, to, amount);
                            }
                            /** @dev Creates `amount` tokens and assigns them to `account`, increasing
                             * the total supply.
                             *
                             * Emits a {Transfer} event with `from` set to the zero address.
                             *
                             * Requirements:
                             *
                             * - `account` cannot be the zero address.
                             */
                            function _mint(address account, uint256 amount) internal virtual {
                                require(account != address(0), "ERC20: mint to the zero address");
                                _beforeTokenTransfer(address(0), account, amount);
                                _totalSupply += amount;
                                unchecked {
                                    // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
                                    _balances[account] += amount;
                                }
                                emit Transfer(address(0), account, amount);
                                _afterTokenTransfer(address(0), account, amount);
                            }
                            /**
                             * @dev Destroys `amount` tokens from `account`, reducing the
                             * total supply.
                             *
                             * Emits a {Transfer} event with `to` set to the zero address.
                             *
                             * Requirements:
                             *
                             * - `account` cannot be the zero address.
                             * - `account` must have at least `amount` tokens.
                             */
                            function _burn(address account, uint256 amount) internal virtual {
                                require(account != address(0), "ERC20: burn from the zero address");
                                _beforeTokenTransfer(account, address(0), amount);
                                uint256 accountBalance = _balances[account];
                                require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
                                unchecked {
                                    _balances[account] = accountBalance - amount;
                                    // Overflow not possible: amount <= accountBalance <= totalSupply.
                                    _totalSupply -= amount;
                                }
                                emit Transfer(account, address(0), amount);
                                _afterTokenTransfer(account, address(0), amount);
                            }
                            /**
                             * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
                             *
                             * This internal function is equivalent to `approve`, and can be used to
                             * e.g. set automatic allowances for certain subsystems, etc.
                             *
                             * Emits an {Approval} event.
                             *
                             * Requirements:
                             *
                             * - `owner` cannot be the zero address.
                             * - `spender` cannot be the zero address.
                             */
                            function _approve(
                                address owner,
                                address spender,
                                uint256 amount
                            ) internal virtual {
                                require(owner != address(0), "ERC20: approve from the zero address");
                                require(spender != address(0), "ERC20: approve to the zero address");
                                _allowances[owner][spender] = amount;
                                emit Approval(owner, spender, amount);
                            }
                            /**
                             * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
                             *
                             * Does not update the allowance amount in case of infinite allowance.
                             * Revert if not enough allowance is available.
                             *
                             * Might emit an {Approval} event.
                             */
                            function _spendAllowance(
                                address owner,
                                address spender,
                                uint256 amount
                            ) internal virtual {
                                uint256 currentAllowance = allowance(owner, spender);
                                if (currentAllowance != type(uint256).max) {
                                    require(currentAllowance >= amount, "ERC20: insufficient allowance");
                                    unchecked {
                                        _approve(owner, spender, currentAllowance - amount);
                                    }
                                }
                            }
                            /**
                             * @dev Hook that is called before any transfer of tokens. This includes
                             * minting and burning.
                             *
                             * Calling conditions:
                             *
                             * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                             * will be transferred to `to`.
                             * - when `from` is zero, `amount` tokens will be minted for `to`.
                             * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
                             * - `from` and `to` are never both zero.
                             *
                             * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                             */
                            function _beforeTokenTransfer(
                                address from,
                                address to,
                                uint256 amount
                            ) internal virtual {}
                            /**
                             * @dev Hook that is called after any transfer of tokens. This includes
                             * minting and burning.
                             *
                             * Calling conditions:
                             *
                             * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                             * has been transferred to `to`.
                             * - when `from` is zero, `amount` tokens have been minted for `to`.
                             * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
                             * - `from` and `to` are never both zero.
                             *
                             * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                             */
                            function _afterTokenTransfer(
                                address from,
                                address to,
                                uint256 amount
                            ) internal virtual {}
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev Interface of the ERC165 standard, as defined in the
                         * https://eips.ethereum.org/EIPS/eip-165[EIP].
                         *
                         * Implementers can declare support of contract interfaces, which can then be
                         * queried by others ({ERC165Checker}).
                         *
                         * For an implementation, see {ERC165}.
                         */
                        interface IERC165 {
                            /**
                             * @dev Returns true if this contract implements the interface defined by
                             * `interfaceId`. See the corresponding
                             * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
                             * to learn more about how these ids are created.
                             *
                             * This function call must use less than 30 000 gas.
                             */
                            function supportsInterface(bytes4 interfaceId) external view returns (bool);
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.5.0;
                        import "./IOFTCore.sol";
                        import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                        /**
                         * @dev Interface of the OFT standard
                         */
                        interface IOFT is IOFTCore, IERC20 {
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.8.0;
                        import "../../lzApp/NonblockingLzApp.sol";
                        import "./IOFTCore.sol";
                        import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
                        abstract contract OFTCore is NonblockingLzApp, ERC165, IOFTCore {
                            using BytesLib for bytes;
                            uint public constant NO_EXTRA_GAS = 0;
                            // packet type
                            uint16 public constant PT_SEND = 0;
                            bool public useCustomAdapterParams;
                            constructor(address _lzEndpoint) NonblockingLzApp(_lzEndpoint) {}
                            function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
                                return interfaceId == type(IOFTCore).interfaceId || super.supportsInterface(interfaceId);
                            }
                            function estimateSendFee(uint16 _dstChainId, bytes calldata _toAddress, uint _amount, bool _useZro, bytes calldata _adapterParams) public view virtual override returns (uint nativeFee, uint zroFee) {
                                // mock the payload for sendFrom()
                                bytes memory payload = abi.encode(PT_SEND, _toAddress, _amount);
                                return lzEndpoint.estimateFees(_dstChainId, address(this), payload, _useZro, _adapterParams);
                            }
                            function sendFrom(address _from, uint16 _dstChainId, bytes calldata _toAddress, uint _amount, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) public payable virtual override {
                                _send(_from, _dstChainId, _toAddress, _amount, _refundAddress, _zroPaymentAddress, _adapterParams);
                            }
                            function setUseCustomAdapterParams(bool _useCustomAdapterParams) public virtual onlyOwner {
                                useCustomAdapterParams = _useCustomAdapterParams;
                                emit SetUseCustomAdapterParams(_useCustomAdapterParams);
                            }
                            function _nonblockingLzReceive(uint16 _srcChainId, bytes memory _srcAddress, uint64 _nonce, bytes memory _payload) internal virtual override {
                                uint16 packetType;
                                assembly {
                                    packetType := mload(add(_payload, 32))
                                }
                                if (packetType == PT_SEND) {
                                    _sendAck(_srcChainId, _srcAddress, _nonce, _payload);
                                } else {
                                    revert("OFTCore: unknown packet type");
                                }
                            }
                            function _send(address _from, uint16 _dstChainId, bytes memory _toAddress, uint _amount, address payable _refundAddress, address _zroPaymentAddress, bytes memory _adapterParams) internal virtual {
                                _checkAdapterParams(_dstChainId, PT_SEND, _adapterParams, NO_EXTRA_GAS);
                                uint amount = _debitFrom(_from, _dstChainId, _toAddress, _amount);
                                bytes memory lzPayload = abi.encode(PT_SEND, _toAddress, amount);
                                _lzSend(_dstChainId, lzPayload, _refundAddress, _zroPaymentAddress, _adapterParams, msg.value);
                                emit SendToChain(_dstChainId, _from, _toAddress, amount);
                            }
                            function _sendAck(uint16 _srcChainId, bytes memory, uint64, bytes memory _payload) internal virtual {
                                (, bytes memory toAddressBytes, uint amount) = abi.decode(_payload, (uint16, bytes, uint));
                                address to = toAddressBytes.toAddress(0);
                                amount = _creditTo(_srcChainId, to, amount);
                                emit ReceiveFromChain(_srcChainId, to, amount);
                            }
                            function _checkAdapterParams(uint16 _dstChainId, uint16 _pkType, bytes memory _adapterParams, uint _extraGas) internal virtual {
                                if (useCustomAdapterParams) {
                                    _checkGasLimit(_dstChainId, _pkType, _adapterParams, _extraGas);
                                } else {
                                    require(_adapterParams.length == 0, "OFTCore: _adapterParams must be empty.");
                                }
                            }
                            function _debitFrom(address _from, uint16 _dstChainId, bytes memory _toAddress, uint _amount) internal virtual returns(uint);
                            function _creditTo(uint16 _srcChainId, address _toAddress, uint _amount) internal virtual returns(uint);
                        }
                        

                        File 6 of 12: Endpoint
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity 0.7.6;
                        import "./interfaces/ILayerZeroReceiver.sol";
                        import "./interfaces/ILayerZeroEndpoint.sol";
                        import "./interfaces/ILayerZeroMessagingLibrary.sol";
                        import "@openzeppelin/contracts/access/Ownable.sol";
                        contract Endpoint is Ownable, ILayerZeroEndpoint {
                            uint16 public immutable chainId;
                            // installed libraries and reserved versions
                            uint16 public constant BLOCK_VERSION = 65535;
                            uint16 public constant DEFAULT_VERSION = 0;
                            uint16 public latestVersion;
                            mapping(uint16 => ILayerZeroMessagingLibrary) public libraryLookup; // version -> ILayerZeroEndpointLibrary
                            // default send/receive libraries
                            uint16 public defaultSendVersion;
                            uint16 public defaultReceiveVersion;
                            ILayerZeroMessagingLibrary public defaultSendLibrary;
                            address public defaultReceiveLibraryAddress;
                            struct LibraryConfig {
                                uint16 sendVersion;
                                uint16 receiveVersion;
                                address receiveLibraryAddress;
                                ILayerZeroMessagingLibrary sendLibrary;
                            }
                            struct StoredPayload {
                                uint64 payloadLength;
                                address dstAddress;
                                bytes32 payloadHash;
                            }
                            // user app config = [uaAddress]
                            mapping(address => LibraryConfig) public uaConfigLookup;
                            // inboundNonce = [srcChainId][srcAddress].
                            mapping(uint16 => mapping(bytes => uint64)) public inboundNonce;
                            // outboundNonce = [dstChainId][srcAddress].
                            mapping(uint16 => mapping(address => uint64)) public outboundNonce;
                            // storedPayload = [srcChainId][srcAddress]
                            mapping(uint16 => mapping(bytes => StoredPayload)) public storedPayload;
                            // library versioning events
                            event NewLibraryVersionAdded(uint16 version);
                            event DefaultSendVersionSet(uint16 version);
                            event DefaultReceiveVersionSet(uint16 version);
                            event UaSendVersionSet(address ua, uint16 version);
                            event UaReceiveVersionSet(address ua, uint16 version);
                            event UaForceResumeReceive(uint16 chainId, bytes srcAddress);
                            // payload events
                            event PayloadCleared(uint16 srcChainId, bytes srcAddress, uint64 nonce, address dstAddress);
                            event PayloadStored(uint16 srcChainId, bytes srcAddress, address dstAddress, uint64 nonce, bytes payload, bytes reason);
                            constructor(uint16 _chainId) {
                                chainId = _chainId;
                            }
                            //---------------------------------------------------------------------------
                            // send and receive nonreentrant lock
                            uint8 internal constant _NOT_ENTERED = 1;
                            uint8 internal constant _ENTERED = 2;
                            uint8 internal _send_entered_state = 1;
                            uint8 internal _receive_entered_state = 1;
                            modifier sendNonReentrant() {
                                require(_send_entered_state == _NOT_ENTERED, "LayerZero: no send reentrancy");
                                _send_entered_state = _ENTERED;
                                _;
                                _send_entered_state = _NOT_ENTERED;
                            }
                            modifier receiveNonReentrant() {
                                require(_receive_entered_state == _NOT_ENTERED, "LayerZero: no receive reentrancy");
                                _receive_entered_state = _ENTERED;
                                _;
                                _receive_entered_state = _NOT_ENTERED;
                            }
                            // BLOCK_VERSION is also a valid version
                            modifier validVersion(uint16 _version) {
                                require(_version <= latestVersion || _version == BLOCK_VERSION, "LayerZero: invalid messaging library version");
                                _;
                            }
                            //---------------------------------------------------------------------------
                            // User Application Calls - Endpoint Interface
                            function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable override sendNonReentrant {
                                LibraryConfig storage uaConfig = uaConfigLookup[msg.sender];
                                uint64 nonce = ++outboundNonce[_dstChainId][msg.sender];
                                _getSendLibrary(uaConfig).send{value: msg.value}(msg.sender, nonce, _dstChainId, _destination, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
                            }
                            //---------------------------------------------------------------------------
                            // authenticated Library (msg.sender) Calls to pass through Endpoint to UA (dstAddress)
                            function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external override receiveNonReentrant {
                                // assert and increment the nonce. no message shuffling
                                require(_nonce == ++inboundNonce[_srcChainId][_srcAddress], "LayerZero: wrong nonce");
                                LibraryConfig storage uaConfig = uaConfigLookup[_dstAddress];
                                // authentication to prevent cross-version message validation
                                // protects against a malicious library from passing arbitrary data
                                if (uaConfig.receiveVersion == DEFAULT_VERSION) {
                                    require(defaultReceiveLibraryAddress == msg.sender, "LayerZero: invalid default library");
                                } else {
                                    require(uaConfig.receiveLibraryAddress == msg.sender, "LayerZero: invalid library");
                                }
                                // block if any message blocking
                                StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                require(sp.payloadHash == bytes32(0), "LayerZero: in message blocking");
                                try ILayerZeroReceiver(_dstAddress).lzReceive{gas: _gasLimit}(_srcChainId, _srcAddress, _nonce, _payload) {
                                    // success, do nothing, end of the message delivery
                                } catch (bytes memory reason) {
                                    // revert nonce if any uncaught errors/exceptions if the ua chooses the blocking mode
                                    storedPayload[_srcChainId][_srcAddress] = StoredPayload(uint64(_payload.length), _dstAddress, keccak256(_payload));
                                    emit PayloadStored(_srcChainId, _srcAddress, _dstAddress, _nonce, _payload, reason);
                                }
                            }
                            function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external override receiveNonReentrant {
                                StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                require(sp.payloadHash != bytes32(0), "LayerZero: no stored payload");
                                require(_payload.length == sp.payloadLength && keccak256(_payload) == sp.payloadHash, "LayerZero: invalid payload");
                                address dstAddress = sp.dstAddress;
                                // empty the storedPayload
                                sp.payloadLength = 0;
                                sp.dstAddress = address(0);
                                sp.payloadHash = bytes32(0);
                                uint64 nonce = inboundNonce[_srcChainId][_srcAddress];
                                ILayerZeroReceiver(dstAddress).lzReceive(_srcChainId, _srcAddress, nonce, _payload);
                                emit PayloadCleared(_srcChainId, _srcAddress, nonce, dstAddress);
                            }
                            //---------------------------------------------------------------------------
                            // Owner Calls, only new library version upgrade (3 steps)
                            // note libraryLookup[0] = 0x0, no library implementation
                            // LIBRARY UPGRADE step 1: set _newLayerZeroLibraryAddress be the new version
                            function newVersion(address _newLayerZeroLibraryAddress) external onlyOwner {
                                require(_newLayerZeroLibraryAddress != address(0x0), "LayerZero: new version cannot be zero address");
                                require(latestVersion < 65535, "LayerZero: can not add new messaging library");
                                latestVersion++;
                                libraryLookup[latestVersion] = ILayerZeroMessagingLibrary(_newLayerZeroLibraryAddress);
                                emit NewLibraryVersionAdded(latestVersion);
                            }
                            // LIBRARY UPGRADE step 2: stop sending messages from the old version
                            function setDefaultSendVersion(uint16 _newDefaultSendVersion) external onlyOwner validVersion(_newDefaultSendVersion) {
                                require(_newDefaultSendVersion != DEFAULT_VERSION, "LayerZero: default send version must > 0");
                                defaultSendVersion = _newDefaultSendVersion;
                                defaultSendLibrary = libraryLookup[defaultSendVersion];
                                emit DefaultSendVersionSet(_newDefaultSendVersion);
                            }
                            // LIBRARY UPGRADE step 3: stop receiving messages from the old version
                            function setDefaultReceiveVersion(uint16 _newDefaultReceiveVersion) external onlyOwner validVersion(_newDefaultReceiveVersion) {
                                require(_newDefaultReceiveVersion != DEFAULT_VERSION, "LayerZero: default receive version must > 0");
                                defaultReceiveVersion = _newDefaultReceiveVersion;
                                defaultReceiveLibraryAddress = address(libraryLookup[defaultReceiveVersion]);
                                emit DefaultReceiveVersionSet(_newDefaultReceiveVersion);
                            }
                            //---------------------------------------------------------------------------
                            // User Application Calls - UA set/get Interface
                            function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external override validVersion(_version) {
                                if (_version == DEFAULT_VERSION) {
                                    require(defaultSendVersion == defaultReceiveVersion, "LayerZero: can not set Config during DEFAULT migration");
                                    _version = defaultSendVersion;
                                }
                                require(_version != BLOCK_VERSION, "LayerZero: can not set config for BLOCK_VERSION");
                                libraryLookup[_version].setConfig(_chainId, msg.sender, _configType, _config);
                            }
                            // Migration step 1: set the send version
                            // Define what library the UA points too
                            function setSendVersion(uint16 _newVersion) external override validVersion(_newVersion) {
                                // write into config
                                LibraryConfig storage uaConfig = uaConfigLookup[msg.sender];
                                uaConfig.sendVersion = _newVersion;
                                // the libraryLookup[BLOCK_VERSION || DEFAULT_VERSION] = 0x0
                                uaConfig.sendLibrary = libraryLookup[_newVersion];
                                emit UaSendVersionSet(msg.sender, _newVersion);
                            }
                            // Migration step 2: set the receive version
                            // after all messages sent from the old version are received
                            // the UA can now safely switch to the new receive version
                            // it is the UA's responsibility make sure all messages from the old version are processed
                            function setReceiveVersion(uint16 _newVersion) external override validVersion(_newVersion) {
                                // write into config
                                LibraryConfig storage uaConfig = uaConfigLookup[msg.sender];
                                uaConfig.receiveVersion = _newVersion;
                                // the libraryLookup[BLOCK_VERSION || DEFAULT_VERSION] = 0x0
                                uaConfig.receiveLibraryAddress = address(libraryLookup[_newVersion]);
                                emit UaReceiveVersionSet(msg.sender, _newVersion);
                            }
                            function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external override {
                                StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                // revert if no messages are cached. safeguard malicious UA behaviour
                                require(sp.payloadHash != bytes32(0), "LayerZero: no stored payload");
                                require(sp.dstAddress == msg.sender, "LayerZero: invalid caller");
                                // empty the storedPayload
                                sp.payloadLength = 0;
                                sp.dstAddress = address(0);
                                sp.payloadHash = bytes32(0);
                                // emit the event with the new nonce
                                emit UaForceResumeReceive(_srcChainId, _srcAddress);
                            }
                            //---------------------------------------------------------------------------
                            // view helper function
                            function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParams) external view override returns (uint nativeFee, uint zroFee) {
                                LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                ILayerZeroMessagingLibrary lib = uaConfig.sendVersion == DEFAULT_VERSION ? defaultSendLibrary : uaConfig.sendLibrary;
                                return lib.estimateFees(_dstChainId, _userApplication, _payload, _payInZRO, _adapterParams);
                            }
                            function _getSendLibrary(LibraryConfig storage uaConfig) internal view returns (ILayerZeroMessagingLibrary) {
                                if (uaConfig.sendVersion == DEFAULT_VERSION) {
                                    // check if the in send-blocking upgrade
                                    require(defaultSendVersion != BLOCK_VERSION, "LayerZero: default in BLOCK_VERSION");
                                    return defaultSendLibrary;
                                } else {
                                    // check if the in send-blocking upgrade
                                    require(uaConfig.sendVersion != BLOCK_VERSION, "LayerZero: in BLOCK_VERSION");
                                    return uaConfig.sendLibrary;
                                }
                            }
                            function getSendLibraryAddress(address _userApplication) external view override returns (address sendLibraryAddress) {
                                LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                uint16 sendVersion = uaConfig.sendVersion;
                                require(sendVersion != BLOCK_VERSION, "LayerZero: send version is BLOCK_VERSION");
                                if (sendVersion == DEFAULT_VERSION) {
                                    require(defaultSendVersion != BLOCK_VERSION, "LayerZero: send version (default) is BLOCK_VERSION");
                                    sendLibraryAddress = address(defaultSendLibrary);
                                } else {
                                    sendLibraryAddress = address(uaConfig.sendLibrary);
                                }
                            }
                            function getReceiveLibraryAddress(address _userApplication) external view override returns (address receiveLibraryAddress) {
                                LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                uint16 receiveVersion = uaConfig.receiveVersion;
                                require(receiveVersion != BLOCK_VERSION, "LayerZero: receive version is BLOCK_VERSION");
                                if (receiveVersion == DEFAULT_VERSION) {
                                    require(defaultReceiveVersion != BLOCK_VERSION, "LayerZero: receive version (default) is BLOCK_VERSION");
                                    receiveLibraryAddress = defaultReceiveLibraryAddress;
                                } else {
                                    receiveLibraryAddress = uaConfig.receiveLibraryAddress;
                                }
                            }
                            function isSendingPayload() external view override returns (bool) {
                                return _send_entered_state == _ENTERED;
                            }
                            function isReceivingPayload() external view override returns (bool) {
                                return _receive_entered_state == _ENTERED;
                            }
                            function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view override returns (uint64) {
                                return inboundNonce[_srcChainId][_srcAddress];
                            }
                            function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view override returns (uint64) {
                                return outboundNonce[_dstChainId][_srcAddress];
                            }
                            function getChainId() external view override returns (uint16) {
                                return chainId;
                            }
                            function getSendVersion(address _userApplication) external view override returns (uint16) {
                                LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                return uaConfig.sendVersion == DEFAULT_VERSION ? defaultSendVersion : uaConfig.sendVersion;
                            }
                            function getReceiveVersion(address _userApplication) external view override returns (uint16) {
                                LibraryConfig storage uaConfig = uaConfigLookup[_userApplication];
                                return uaConfig.receiveVersion == DEFAULT_VERSION ? defaultReceiveVersion : uaConfig.receiveVersion;
                            }
                            function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view override validVersion(_version) returns (bytes memory) {
                                if (_version == DEFAULT_VERSION) {
                                    require(defaultSendVersion == defaultReceiveVersion, "LayerZero: no DEFAULT config while migration");
                                    _version = defaultSendVersion;
                                }
                                require(_version != BLOCK_VERSION, "LayerZero: can not get config for BLOCK_VERSION");
                                return libraryLookup[_version].getConfig(_chainId, _userApplication, _configType);
                            }
                            function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view override returns (bool) {
                                StoredPayload storage sp = storedPayload[_srcChainId][_srcAddress];
                                return sp.payloadHash != bytes32(0);
                            }
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.5.0;
                        interface ILayerZeroReceiver {
                            // @notice LayerZero endpoint will invoke this function to deliver the message on the destination
                            // @param _srcChainId - the source endpoint identifier
                            // @param _srcAddress - the source sending contract address from the source chain
                            // @param _nonce - the ordered message nonce
                            // @param _payload - the signed payload is the UA bytes has encoded to be sent
                            function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) external;
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.5.0;
                        import "./ILayerZeroUserApplicationConfig.sol";
                        interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
                            // @notice send a LayerZero message to the specified address at a LayerZero endpoint.
                            // @param _dstChainId - the destination chain identifier
                            // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
                            // @param _payload - a custom bytes payload to send to the destination contract
                            // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
                            // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
                            // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
                            function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                            // @notice used by the messaging library to publish verified payload
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source contract (as bytes) at the source chain
                            // @param _dstAddress - the address on destination chain
                            // @param _nonce - the unbound message ordering nonce
                            // @param _gasLimit - the gas limit for external contract execution
                            // @param _payload - verified payload to send to the destination contract
                            function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;
                            // @notice get the inboundNonce of a receiver from a source chain which could be EVM or non-EVM chain
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
                            // @notice get the outboundNonce from this source chain which, consequently, is always an EVM
                            // @param _srcAddress - the source chain contract address
                            function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
                            // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
                            // @param _dstChainId - the destination chain identifier
                            // @param _userApplication - the user app address on this EVM chain
                            // @param _payload - the custom message to send over LayerZero
                            // @param _payInZRO - if false, user app pays the protocol fee in native token
                            // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
                            function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                            // @notice get this Endpoint's immutable source identifier
                            function getChainId() external view returns (uint16);
                            // @notice the interface to retry failed message on this Endpoint destination
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            // @param _payload - the payload to be retried
                            function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;
                            // @notice query if any STORED payload (message blocking) at the endpoint.
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
                            // @notice query if the _libraryAddress is valid for sending msgs.
                            // @param _userApplication - the user app address on this EVM chain
                            function getSendLibraryAddress(address _userApplication) external view returns (address);
                            // @notice query if the _libraryAddress is valid for receiving msgs.
                            // @param _userApplication - the user app address on this EVM chain
                            function getReceiveLibraryAddress(address _userApplication) external view returns (address);
                            // @notice query if the non-reentrancy guard for send() is on
                            // @return true if the guard is on. false otherwise
                            function isSendingPayload() external view returns (bool);
                            // @notice query if the non-reentrancy guard for receive() is on
                            // @return true if the guard is on. false otherwise
                            function isReceivingPayload() external view returns (bool);
                            // @notice get the configuration of the LayerZero messaging library of the specified version
                            // @param _version - messaging library version
                            // @param _chainId - the chainId for the pending config change
                            // @param _userApplication - the contract address of the user application
                            // @param _configType - type of configuration. every messaging library has its own convention.
                            function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                            // @notice get the send() LayerZero messaging library version
                            // @param _userApplication - the contract address of the user application
                            function getSendVersion(address _userApplication) external view returns (uint16);
                            // @notice get the lzReceive() LayerZero messaging library version
                            // @param _userApplication - the contract address of the user application
                            function getReceiveVersion(address _userApplication) external view returns (uint16);
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.7.0;
                        import "./ILayerZeroUserApplicationConfig.sol";
                        interface ILayerZeroMessagingLibrary {
                            // send(), messages will be inflight.
                            function send(address _userApplication, uint64 _lastNonce, uint16 _chainId, bytes calldata _destination, bytes calldata _payload, address payable refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                            // estimate native fee at the send side
                            function estimateFees(uint16 _chainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                            //---------------------------------------------------------------------------
                            // setConfig / getConfig are User Application (UA) functions to specify Oracle, Relayer, blockConfirmations, libraryVersion
                            function setConfig(uint16 _chainId, address _userApplication, uint _configType, bytes calldata _config) external;
                            function getConfig(uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        import "../utils/Context.sol";
                        /**
                         * @dev Contract module which provides a basic access control mechanism, where
                         * there is an account (an owner) that can be granted exclusive access to
                         * specific functions.
                         *
                         * By default, the owner account will be the one that deploys the contract. This
                         * can later be changed with {transferOwnership}.
                         *
                         * This module is used through inheritance. It will make available the modifier
                         * `onlyOwner`, which can be applied to your functions to restrict their use to
                         * the owner.
                         */
                        abstract contract Ownable is Context {
                            address private _owner;
                            event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                            /**
                             * @dev Initializes the contract setting the deployer as the initial owner.
                             */
                            constructor () {
                                address msgSender = _msgSender();
                                _owner = msgSender;
                                emit OwnershipTransferred(address(0), msgSender);
                            }
                            /**
                             * @dev Returns the address of the current owner.
                             */
                            function owner() public view virtual returns (address) {
                                return _owner;
                            }
                            /**
                             * @dev Throws if called by any account other than the owner.
                             */
                            modifier onlyOwner() {
                                require(owner() == _msgSender(), "Ownable: caller is not the owner");
                                _;
                            }
                            /**
                             * @dev Leaves the contract without owner. It will not be possible to call
                             * `onlyOwner` functions anymore. Can only be called by the current owner.
                             *
                             * NOTE: Renouncing ownership will leave the contract without an owner,
                             * thereby removing any functionality that is only available to the owner.
                             */
                            function renounceOwnership() public virtual onlyOwner {
                                emit OwnershipTransferred(_owner, address(0));
                                _owner = address(0);
                            }
                            /**
                             * @dev Transfers ownership of the contract to a new account (`newOwner`).
                             * Can only be called by the current owner.
                             */
                            function transferOwnership(address newOwner) public virtual onlyOwner {
                                require(newOwner != address(0), "Ownable: new owner is the zero address");
                                emit OwnershipTransferred(_owner, newOwner);
                                _owner = newOwner;
                            }
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.5.0;
                        interface ILayerZeroUserApplicationConfig {
                            // @notice set the configuration of the LayerZero messaging library of the specified version
                            // @param _version - messaging library version
                            // @param _chainId - the chainId for the pending config change
                            // @param _configType - type of configuration. every messaging library has its own convention.
                            // @param _config - configuration in the bytes. can encode arbitrary content.
                            function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;
                            // @notice set the send() LayerZero messaging library version to _version
                            // @param _version - new messaging library version
                            function setSendVersion(uint16 _version) external;
                            // @notice set the lzReceive() LayerZero messaging library version to _version
                            // @param _version - new messaging library version
                            function setReceiveVersion(uint16 _version) external;
                            // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
                            // @param _srcChainId - the chainId of the source chain
                            // @param _srcAddress - the contract address of the source contract at the source chain
                            function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.6.0 <0.8.0;
                        /*
                         * @dev Provides information about the current execution context, including the
                         * sender of the transaction and its data. While these are generally available
                         * via msg.sender and msg.data, they should not be accessed in such a direct
                         * manner, since when dealing with GSN meta-transactions the account sending and
                         * paying for execution may not be the actual sender (as far as an application
                         * is concerned).
                         *
                         * This contract is only required for intermediate, library-like contracts.
                         */
                        abstract contract Context {
                            function _msgSender() internal view virtual returns (address payable) {
                                return msg.sender;
                            }
                            function _msgData() internal view virtual returns (bytes memory) {
                                this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                                return msg.data;
                            }
                        }
                        

                        File 7 of 12: UltraLightNodeV2
                        {"Address.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n    /**\n     * @dev Returns true if `account` is a contract.\n     *\n     * [IMPORTANT]\n     * ====\n     * It is unsafe to assume that an address for which this function returns\n     * false is an externally-owned account (EOA) and not a contract.\n     *\n     * Among others, `isContract` will return false for the following\n     * types of addresses:\n     *\n     *  - an externally-owned account\n     *  - a contract in construction\n     *  - an address where a contract will be created\n     *  - an address where a contract lived, but was destroyed\n     * ====\n     */\n    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize, which returns 0 for contracts in\n        // construction, since the code is only stored at the end of the\n        // constructor execution.\n\n        uint256 size;\n        // solhint-disable-next-line no-inline-assembly\n        assembly { size := extcodesize(account) }\n        return size \u003e 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity\u0027s `transfer`: sends `amount` wei to\n     * `recipient`, forwarding all available gas and reverting on errors.\n     *\n     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n     * of certain opcodes, possibly making contracts go over the 2300 gas limit\n     * imposed by `transfer`, making them unable to receive funds via\n     * `transfer`. {sendValue} removes this limitation.\n     *\n     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n     *\n     * IMPORTANT: because control is transferred to `recipient`, care must be\n     * taken to not create reentrancy vulnerabilities. Consider using\n     * {ReentrancyGuard} or the\n     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n     */\n    function sendValue(address payable recipient, uint256 amount) internal {\n        require(address(this).balance \u003e= amount, \"Address: insufficient balance\");\n\n        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\n        (bool success, ) = recipient.call{ value: amount }(\"\");\n        require(success, \"Address: unable to send value, recipient may have reverted\");\n    }\n\n    /**\n     * @dev Performs a Solidity function call using a low level `call`. A\n     * plain`call` is an unsafe replacement for a function call: use this\n     * function instead.\n     *\n     * If `target` reverts with a revert reason, it is bubbled up by this\n     * function (like regular Solidity function calls).\n     *\n     * Returns the raw returned data. To convert to the expected return value,\n     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n     *\n     * Requirements:\n     *\n     * - `target` must be a contract.\n     * - calling `target` with `data` must not revert.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n      return functionCall(target, data, \"Address: low-level call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n     * `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but also transferring `value` wei to `target`.\n     *\n     * Requirements:\n     *\n     * - the calling contract must have an ETH balance of at least `value`.\n     * - the called Solidity function must be `payable`.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n     * with `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {\n        require(address(this).balance \u003e= value, \"Address: insufficient balance for call\");\n        require(isContract(target), \"Address: call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.call{ value: value }(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n        return functionStaticCall(target, data, \"Address: low-level static call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\n            // Look for revert reason and bubble it up if present\n            if (returndata.length \u003e 0) {\n                // The easiest way to bubble the revert reason is using memory via assembly\n\n                // solhint-disable-next-line no-inline-assembly\n                assembly {\n                    let returndata_size := mload(returndata)\n                    revert(add(32, returndata), returndata_size)\n                }\n            } else {\n                revert(errorMessage);\n            }\n        }\n    }\n}\n"},"Buffer.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\n// https://github.com/ensdomains/buffer\n\npragma solidity ^0.7.0;\n\n/**\n * @dev A library for working with mutable byte buffers in Solidity.\n *\n * Byte buffers are mutable and expandable, and provide a variety of primitives\n * for writing to them. At any time you can fetch a bytes object containing the\n * current contents of the buffer. The bytes object should not be stored between\n * operations, as it may change due to resizing of the buffer.\n */\nlibrary Buffer {\n    /**\n     * @dev Represents a mutable buffer. Buffers have a current value (buf) and\n     *      a capacity. The capacity may be longer than the current value, in\n     *      which case it can be extended without the need to allocate more memory.\n     */\n    struct buffer {\n        bytes buf;\n        uint capacity;\n    }\n\n    /**\n     * @dev Initializes a buffer with an initial capacity.a co\n     * @param buf The buffer to initialize.\n     * @param capacity The number of bytes of space to allocate the buffer.\n     * @return The buffer, for chaining.\n     */\n    function init(buffer memory buf, uint capacity) internal pure returns (buffer memory) {\n        if (capacity % 32 != 0) {\n            capacity += 32 - (capacity % 32);\n        }\n        // Allocate space for the buffer data\n        buf.capacity = capacity;\n        assembly {\n            let ptr := mload(0x40)\n            mstore(buf, ptr)\n            mstore(ptr, 0)\n            mstore(0x40, add(32, add(ptr, capacity)))\n        }\n        return buf;\n    }\n\n\n    /**\n     * @dev Writes a byte string to a buffer. Resizes if doing so would exceed\n     *      the capacity of the buffer.\n     * @param buf The buffer to append to.\n     * @param off The start offset to write to.\n     * @param rawData The data to append.\n     * @param len The number of bytes to copy.\n     * @return The original buffer, for chaining.\n     */\n    function writeRawBytes(\n        buffer memory buf,\n        uint off,\n        bytes memory rawData,\n        uint offData,\n        uint len\n    ) internal pure returns (buffer memory) {\n        if (off + len \u003e buf.capacity) {\n            resize(buf, max(buf.capacity, len + off) * 2);\n        }\n\n        uint dest;\n        uint src;\n        assembly {\n            // Memory address of the buffer data\n            let bufptr := mload(buf)\n            // Length of existing buffer data\n            let buflen := mload(bufptr)\n            // Start address = buffer address + offset + sizeof(buffer length)\n            dest := add(add(bufptr, 32), off)\n            // Update buffer length if we\u0027re extending it\n            if gt(add(len, off), buflen) {\n                mstore(bufptr, add(len, off))\n            }\n            src := add(rawData, offData)\n        }\n\n        // Copy word-length chunks while possible\n        for (; len \u003e= 32; len -= 32) {\n            assembly {\n                mstore(dest, mload(src))\n            }\n            dest += 32;\n            src += 32;\n        }\n\n        // Copy remaining bytes\n        uint mask = 256**(32 - len) - 1;\n        assembly {\n            let srcpart := and(mload(src), not(mask))\n            let destpart := and(mload(dest), mask)\n            mstore(dest, or(destpart, srcpart))\n        }\n\n        return buf;\n    }\n\n    /**\n     * @dev Writes a byte string to a buffer. Resizes if doing so would exceed\n     *      the capacity of the buffer.\n     * @param buf The buffer to append to.\n     * @param off The start offset to write to.\n     * @param data The data to append.\n     * @param len The number of bytes to copy.\n     * @return The original buffer, for chaining.\n     */\n    function write(buffer memory buf, uint off, bytes memory data, uint len) internal pure returns (buffer memory) {\n        require(len \u003c= data.length);\n\n        if (off + len \u003e buf.capacity) {\n            resize(buf, max(buf.capacity, len + off) * 2);\n        }\n\n        uint dest;\n        uint src;\n        assembly {\n        // Memory address of the buffer data\n            let bufptr := mload(buf)\n        // Length of existing buffer data\n            let buflen := mload(bufptr)\n        // Start address = buffer address + offset + sizeof(buffer length)\n            dest := add(add(bufptr, 32), off)\n        // Update buffer length if we\u0027re extending it\n            if gt(add(len, off), buflen) {\n                mstore(bufptr, add(len, off))\n            }\n            src := add(data, 32)\n        }\n\n        // Copy word-length chunks while possible\n        for (; len \u003e= 32; len -= 32) {\n            assembly {\n                mstore(dest, mload(src))\n            }\n            dest += 32;\n            src += 32;\n        }\n\n        // Copy remaining bytes\n        uint mask = 256**(32 - len) - 1;\n        assembly {\n            let srcpart := and(mload(src), not(mask))\n            let destpart := and(mload(dest), mask)\n            mstore(dest, or(destpart, srcpart))\n        }\n\n        return buf;\n    }\n\n    function append(buffer memory buf, bytes memory data) internal pure returns (buffer memory) {\n        return write(buf, buf.buf.length, data, data.length);\n    }\n\n    function resize(buffer memory buf, uint capacity) private pure {\n        bytes memory oldbuf = buf.buf;\n        init(buf, capacity);\n        append(buf, oldbuf);\n    }\n\n    function max(uint a, uint b) private pure returns (uint) {\n        if (a \u003e b) {\n            return a;\n        }\n        return b;\n    }\n}\n"},"Context.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity \u003e=0.6.0 \u003c0.8.0;\n\n/*\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with GSN meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n    function _msgSender() internal view virtual returns (address payable) {\n        return msg.sender;\n    }\n\n    function _msgData() internal view virtual returns (bytes memory) {\n        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691\n        return msg.data;\n    }\n}\n"},"IERC20.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n    /**\n     * @dev Returns the amount of tokens in existence.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns the amount of tokens owned by `account`.\n     */\n    function balanceOf(address account) external view returns (uint256);\n\n    /**\n     * @dev Moves `amount` tokens from the caller\u0027s account to `recipient`.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transfer(address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Returns the remaining number of tokens that `spender` will be\n     * allowed to spend on behalf of `owner` through {transferFrom}. This is\n     * zero by default.\n     *\n     * This value changes when {approve} or {transferFrom} are called.\n     */\n    function allowance(address owner, address spender) external view returns (uint256);\n\n    /**\n     * @dev Sets `amount` as the allowance of `spender` over the caller\u0027s tokens.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * IMPORTANT: Beware that changing an allowance with this method brings the risk\n     * that someone may use both the old and the new allowance by unfortunate\n     * transaction ordering. One possible solution to mitigate this race\n     * condition is to first reduce the spender\u0027s allowance to 0 and set the\n     * desired value afterwards:\n     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address spender, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Moves `amount` tokens from `sender` to `recipient` using the\n     * allowance mechanism. `amount` is then deducted from the caller\u0027s\n     * allowance.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Emitted when `value` tokens are moved from one account (`from`) to\n     * another (`to`).\n     *\n     * Note that `value` may be zero.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 value);\n\n    /**\n     * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n     * a call to {approve}. `value` is the new allowance.\n     */\n    event Approval(address indexed owner, address indexed spender, uint256 value);\n}\n"},"ILayerZeroEndpoint.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\nimport \"./ILayerZeroUserApplicationConfig.sol\";\n\ninterface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {\n    // @notice send a LayerZero message to the specified address at a LayerZero endpoint.\n    // @param _dstChainId - the destination chain identifier\n    // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains\n    // @param _payload - a custom bytes payload to send to the destination contract\n    // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address\n    // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction\n    // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination\n    function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;\n\n    // @notice used by the messaging library to publish verified payload\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source contract (as bytes) at the source chain\n    // @param _dstAddress - the address on destination chain\n    // @param _nonce - the unbound message ordering nonce\n    // @param _gasLimit - the gas limit for external contract execution\n    // @param _payload - verified payload to send to the destination contract\n    function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;\n\n    // @notice get the inboundNonce of a receiver from a source chain which could be EVM or non-EVM chain\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source chain contract address\n    function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);\n\n    // @notice get the outboundNonce from this source chain which, consequently, is always an EVM\n    // @param _srcAddress - the source chain contract address\n    function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);\n\n    // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery\n    // @param _dstChainId - the destination chain identifier\n    // @param _userApplication - the user app address on this EVM chain\n    // @param _payload - the custom message to send over LayerZero\n    // @param _payInZRO - if false, user app pays the protocol fee in native token\n    // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain\n    function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);\n\n    // @notice get this Endpoint\u0027s immutable source identifier\n    function getChainId() external view returns (uint16);\n\n    // @notice the interface to retry failed message on this Endpoint destination\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source chain contract address\n    // @param _payload - the payload to be retried\n    function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;\n\n    // @notice query if any STORED payload (message blocking) at the endpoint.\n    // @param _srcChainId - the source chain identifier\n    // @param _srcAddress - the source chain contract address\n    function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);\n\n    // @notice query if the _libraryAddress is valid for sending msgs.\n    // @param _userApplication - the user app address on this EVM chain\n    function getSendLibraryAddress(address _userApplication) external view returns (address);\n\n    // @notice query if the _libraryAddress is valid for receiving msgs.\n    // @param _userApplication - the user app address on this EVM chain\n    function getReceiveLibraryAddress(address _userApplication) external view returns (address);\n\n    // @notice query if the non-reentrancy guard for send() is on\n    // @return true if the guard is on. false otherwise\n    function isSendingPayload() external view returns (bool);\n\n    // @notice query if the non-reentrancy guard for receive() is on\n    // @return true if the guard is on. false otherwise\n    function isReceivingPayload() external view returns (bool);\n\n    // @notice get the configuration of the LayerZero messaging library of the specified version\n    // @param _version - messaging library version\n    // @param _chainId - the chainId for the pending config change\n    // @param _userApplication - the contract address of the user application\n    // @param _configType - type of configuration. every messaging library has its own convention.\n    function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);\n\n    // @notice get the send() LayerZero messaging library version\n    // @param _userApplication - the contract address of the user application\n    function getSendVersion(address _userApplication) external view returns (uint16);\n\n    // @notice get the lzReceive() LayerZero messaging library version\n    // @param _userApplication - the contract address of the user application\n    function getReceiveVersion(address _userApplication) external view returns (uint16);\n}\n"},"ILayerZeroMessagingLibrary.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\nimport \"./ILayerZeroUserApplicationConfig.sol\";\n\ninterface ILayerZeroMessagingLibrary {\n    // send(), messages will be inflight.\n    function send(address _userApplication, uint64 _lastNonce, uint16 _chainId, bytes calldata _destination, bytes calldata _payload, address payable refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;\n\n    // estimate native fee at the send side\n    function estimateFees(uint16 _chainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);\n\n    //---------------------------------------------------------------------------\n    // setConfig / getConfig are User Application (UA) functions to specify Oracle, Relayer, blockConfirmations, libraryVersion\n    function setConfig(uint16 _chainId, address _userApplication, uint _configType, bytes calldata _config) external;\n\n    function getConfig(uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);\n}\n"},"ILayerZeroMessagingLibraryV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\nimport \"./ILayerZeroUserApplicationConfig.sol\";\nimport \"./ILayerZeroMessagingLibrary.sol\";\n\ninterface ILayerZeroMessagingLibraryV2 is ILayerZeroMessagingLibrary {\n    function getOutboundNonce(uint16 _chainId, bytes calldata _path) external view returns (uint64);\n}\n"},"ILayerZeroOracleV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\ninterface ILayerZeroOracleV2 {\n    // @notice query price and assign jobs at the same time\n    // @param _dstChainId - the destination endpoint identifier\n    // @param _outboundProofType - the proof type identifier to specify proof to be relayed\n    // @param _outboundBlockConfirmation - block confirmation delay before relaying blocks\n    // @param _userApplication - the source sending contract address\n    function assignJob(uint16 _dstChainId, uint16 _outboundProofType, uint64 _outboundBlockConfirmation, address _userApplication) external returns (uint price);\n\n    // @notice query the oracle price for relaying block information to the destination chain\n    // @param _dstChainId the destination endpoint identifier\n    // @param _outboundProofType the proof type identifier to specify the data to be relayed\n    // @param _outboundBlockConfirmation - block confirmation delay before relaying blocks\n    // @param _userApplication - the source sending contract address\n    function getFee(uint16 _dstChainId, uint16 _outboundProofType, uint64 _outboundBlockConfirmation, address _userApplication) external view returns (uint price);\n\n    // @notice withdraw the accrued fee in ultra light node\n    // @param _to - the fee receiver\n    // @param _amount - the withdrawal amount\n    function withdrawFee(address payable _to, uint _amount) external;\n}\n"},"ILayerZeroReceiver.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\ninterface ILayerZeroReceiver {\n    // @notice LayerZero endpoint will invoke this function to deliver the message on the destination\n    // @param _srcChainId - the source endpoint identifier\n    // @param _srcAddress - the source sending contract address from the source chain\n    // @param _nonce - the ordered message nonce\n    // @param _payload - the signed payload is the UA bytes has encoded to be sent\n    function lzReceive(uint16 _srcChainId, bytes calldata _srcAddress, uint64 _nonce, bytes calldata _payload) external;\n}\n"},"ILayerZeroRelayerV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\n\ninterface ILayerZeroRelayerV2 {\n    // @notice query price and assign jobs at the same time\n    // @param _dstChainId - the destination endpoint identifier\n    // @param _outboundProofType - the proof type identifier to specify proof to be relayed\n    // @param _userApplication - the source sending contract address. relayers may apply price discrimination to user apps\n    // @param _payloadSize - the length of the payload. it is an indicator of gas usage for relaying cross-chain messages\n    // @param _adapterParams - optional parameters for extra service plugins, e.g. sending dust tokens at the destination chain\n    function assignJob(uint16 _dstChainId, uint16 _outboundProofType, address _userApplication, uint _payloadSize, bytes calldata _adapterParams) external returns (uint price);\n\n    // @notice query the relayer price for relaying the payload and its proof to the destination chain\n    // @param _dstChainId - the destination endpoint identifier\n    // @param _outboundProofType - the proof type identifier to specify proof to be relayed\n    // @param _userApplication - the source sending contract address. relayers may apply price discrimination to user apps\n    // @param _payloadSize - the length of the payload. it is an indicator of gas usage for relaying cross-chain messages\n    // @param _adapterParams - optional parameters for extra service plugins, e.g. sending dust tokens at the destination chain\n    function getFee(uint16 _dstChainId, uint16 _outboundProofType, address _userApplication, uint _payloadSize, bytes calldata _adapterParams) external view returns (uint price);\n\n    // @notice withdraw the accrued fee in ultra light node\n    // @param _to - the fee receiver\n    // @param _amount - the withdrawal amount\n    function withdrawFee(address payable _to, uint _amount) external;\n}\n"},"ILayerZeroTreasury.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\ninterface ILayerZeroTreasury {\n    function getFees(bool payInZro, uint relayerFee, uint oracleFee) external view returns (uint);\n}\n"},"ILayerZeroUltraLightNodeV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\npragma abicoder v2;\n\ninterface ILayerZeroUltraLightNodeV2 {\n    // Relayer functions\n    function validateTransactionProof(uint16 _srcChainId, address _dstAddress, uint _gasLimit, bytes32 _lookupHash, bytes32 _blockData, bytes calldata _transactionProof) external;\n\n    // an Oracle delivers the block data using updateHash()\n    function updateHash(uint16 _srcChainId, bytes32 _lookupHash, uint _confirmations, bytes32 _blockData) external;\n\n    // can only withdraw the receivable of the msg.sender\n    function withdrawNative(address payable _to, uint _amount) external;\n\n    function withdrawZRO(address _to, uint _amount) external;\n\n    // view functions\n    function getAppConfig(uint16 _remoteChainId, address _userApplicationAddress) external view returns (ApplicationConfiguration memory);\n\n    function accruedNativeFee(address _address) external view returns (uint);\n\n    struct ApplicationConfiguration {\n        uint16 inboundProofLibraryVersion;\n        uint64 inboundBlockConfirmations;\n        address relayer;\n        uint16 outboundProofType;\n        uint64 outboundBlockConfirmations;\n        address oracle;\n    }\n\n    event HashReceived(uint16 indexed srcChainId, address indexed oracle, bytes32 lookupHash, bytes32 blockData, uint confirmations);\n    event RelayerParams(bytes adapterParams, uint16 outboundProofType);\n    event Packet(bytes payload);\n    event InvalidDst(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);\n    event PacketReceived(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);\n    event AppConfigUpdated(address indexed userApplication, uint indexed configType, bytes newConfig);\n    event AddInboundProofLibraryForChain(uint16 indexed chainId, address lib);\n    event EnableSupportedOutboundProof(uint16 indexed chainId, uint16 proofType);\n    event SetChainAddressSize(uint16 indexed chainId, uint size);\n    event SetDefaultConfigForChainId(uint16 indexed chainId, uint16 inboundProofLib, uint64 inboundBlockConfirm, address relayer, uint16 outboundProofType, uint64 outboundBlockConfirm, address oracle);\n    event SetDefaultAdapterParamsForChainId(uint16 indexed chainId, uint16 indexed proofType, bytes adapterParams);\n    event SetLayerZeroToken(address indexed tokenAddress);\n    event SetRemoteUln(uint16 indexed chainId, bytes32 uln);\n    event SetTreasury(address indexed treasuryAddress);\n    event WithdrawZRO(address indexed msgSender, address indexed to, uint amount);\n    event WithdrawNative(address indexed msgSender, address indexed to, uint amount);\n}\n"},"ILayerZeroUserApplicationConfig.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.5.0;\n\ninterface ILayerZeroUserApplicationConfig {\n    // @notice set the configuration of the LayerZero messaging library of the specified version\n    // @param _version - messaging library version\n    // @param _chainId - the chainId for the pending config change\n    // @param _configType - type of configuration. every messaging library has its own convention.\n    // @param _config - configuration in the bytes. can encode arbitrary content.\n    function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;\n\n    // @notice set the send() LayerZero messaging library version to _version\n    // @param _version - new messaging library version\n    function setSendVersion(uint16 _version) external;\n\n    // @notice set the lzReceive() LayerZero messaging library version to _version\n    // @param _version - new messaging library version\n    function setReceiveVersion(uint16 _version) external;\n\n    // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload\n    // @param _srcChainId - the chainId of the source chain\n    // @param _srcAddress - the contract address of the source contract at the source chain\n    function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;\n}\n"},"ILayerZeroValidationLibrary.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity \u003e=0.7.0;\npragma abicoder v2;\n\nimport \"./LayerZeroPacket.sol\";\n\ninterface ILayerZeroValidationLibrary {\n    function validateProof(bytes32 blockData, bytes calldata _data, uint _remoteAddressSize) external returns (LayerZeroPacket.Packet memory packet);\n}\n"},"LayerZeroPacket.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity 0.7.6;\n\nimport \"./Buffer.sol\";\nimport \"./SafeMath.sol\";\n\nlibrary LayerZeroPacket {\n    using Buffer for Buffer.buffer;\n    using SafeMath for uint;\n\n    struct Packet {\n        uint16 srcChainId;\n        uint16 dstChainId;\n        uint64 nonce;\n        address dstAddress;\n        bytes srcAddress;\n        bytes32 ulnAddress;\n        bytes payload;\n    }\n\n    function getPacket(\n        bytes memory data,\n        uint16 srcChain,\n        uint sizeOfSrcAddress,\n        bytes32 ulnAddress\n    ) internal pure returns (LayerZeroPacket.Packet memory) {\n        uint16 dstChainId;\n        address dstAddress;\n        uint size;\n        uint64 nonce;\n\n        // The log consists of the destination chain id and then a bytes payload\n        //      0--------------------------------------------31\n        // 0   |  total bytes size\n        // 32  |  destination chain id\n        // 64  |  bytes offset\n        // 96  |  bytes array size\n        // 128 |  payload\n        assembly {\n            dstChainId := mload(add(data, 32))\n            size := mload(add(data, 96)) /// size of the byte array\n            nonce := mload(add(data, 104)) // offset to convert to uint64  128  is index -24\n            dstAddress := mload(add(data, sub(add(128, sizeOfSrcAddress), 4))) // offset to convert to address 12 -8\n        }\n\n        Buffer.buffer memory srcAddressBuffer;\n        srcAddressBuffer.init(sizeOfSrcAddress);\n        srcAddressBuffer.writeRawBytes(0, data, 136, sizeOfSrcAddress); // 128 + 8\n\n        uint payloadSize = size.sub(28).sub(sizeOfSrcAddress);\n        Buffer.buffer memory payloadBuffer;\n        payloadBuffer.init(payloadSize);\n        payloadBuffer.writeRawBytes(0, data, sizeOfSrcAddress.add(156), payloadSize); // 148 + 8\n        return LayerZeroPacket.Packet(srcChain, dstChainId, nonce, dstAddress, srcAddressBuffer.buf, ulnAddress, payloadBuffer.buf);\n    }\n\n    function getPacketV2(\n        bytes memory data,\n        uint sizeOfSrcAddress,\n        bytes32 ulnAddress\n    ) internal pure returns (LayerZeroPacket.Packet memory) {\n        // packet def: abi.encodePacked(nonce, srcChain, srcAddress, dstChain, dstAddress, payload);\n        // data def: abi.encode(packet) = offset(32) + length(32) + packet\n        //              if from EVM\n        // 0 - 31       0 - 31          |  total bytes size\n        // 32 - 63      32 - 63         |  location\n        // 64 - 95      64 - 95         |  size of the packet\n        // 96 - 103     96 - 103        |  nonce\n        // 104 - 105    104 - 105       |  srcChainId\n        // 106 - P      106 - 125       |  srcAddress, where P = 106 + sizeOfSrcAddress - 1,\n        // P+1 - P+2    126 - 127       |  dstChainId\n        // P+3 - P+22   128 - 147       |  dstAddress\n        // P+23 - END   148 - END       |  payload\n\n        // decode the packet\n        uint256 realSize;\n        uint64 nonce;\n        uint16 srcChain;\n        uint16 dstChain;\n        address dstAddress;\n        assembly {\n            realSize := mload(add(data, 64))\n            nonce := mload(add(data, 72)) // 104 - 32\n            srcChain := mload(add(data, 74)) // 106 - 32\n            dstChain := mload(add(data, add(76, sizeOfSrcAddress))) // P + 3 - 32 = 105 + size + 3 - 32 = 76 + size\n            dstAddress := mload(add(data, add(96, sizeOfSrcAddress))) // P + 23 - 32 = 105 + size + 23 - 32 = 96 + size\n        }\n\n        require(srcChain != 0, \"LayerZeroPacket: invalid packet\");\n\n        Buffer.buffer memory srcAddressBuffer;\n        srcAddressBuffer.init(sizeOfSrcAddress);\n        srcAddressBuffer.writeRawBytes(0, data, 106, sizeOfSrcAddress);\n\n        uint nonPayloadSize = sizeOfSrcAddress.add(32);// 2 + 2 + 8 + 20, 32 + 20 = 52 if sizeOfSrcAddress == 20\n        uint payloadSize = realSize.sub(nonPayloadSize);\n        Buffer.buffer memory payloadBuffer;\n        payloadBuffer.init(payloadSize);\n        payloadBuffer.writeRawBytes(0, data, nonPayloadSize.add(96), payloadSize);\n\n        return LayerZeroPacket.Packet(srcChain, dstChain, nonce, dstAddress, srcAddressBuffer.buf, ulnAddress, payloadBuffer.buf);\n    }\n\n    function getPacketV3(\n        bytes memory data,\n        uint sizeOfSrcAddress,\n        bytes32 ulnAddress\n    ) internal pure returns (LayerZeroPacket.Packet memory) {\n        // data def: abi.encodePacked(nonce, srcChain, srcAddress, dstChain, dstAddress, payload);\n        //              if from EVM\n        // 0 - 31       0 - 31          |  total bytes size\n        // 32 - 39      32 - 39         |  nonce\n        // 40 - 41      40 - 41         |  srcChainId\n        // 42 - P       42 - 61         |  srcAddress, where P = 41 + sizeOfSrcAddress,\n        // P+1 - P+2    62 - 63         |  dstChainId\n        // P+3 - P+22   64 - 83         |  dstAddress\n        // P+23 - END   84 - END        |  payload\n\n        // decode the packet\n        uint256 realSize = data.length;\n        uint nonPayloadSize = sizeOfSrcAddress.add(32);// 2 + 2 + 8 + 20, 32 + 20 = 52 if sizeOfSrcAddress == 20\n        require(realSize \u003e= nonPayloadSize, \"LayerZeroPacket: invalid packet\");\n        uint payloadSize = realSize - nonPayloadSize;\n\n        uint64 nonce;\n        uint16 srcChain;\n        uint16 dstChain;\n        address dstAddress;\n        assembly {\n            nonce := mload(add(data, 8)) // 40 - 32\n            srcChain := mload(add(data, 10)) // 42 - 32\n            dstChain := mload(add(data, add(12, sizeOfSrcAddress))) // P + 3 - 32 = 41 + size + 3 - 32 = 12 + size\n            dstAddress := mload(add(data, add(32, sizeOfSrcAddress))) // P + 23 - 32 = 41 + size + 23 - 32 = 32 + size\n        }\n\n        require(srcChain != 0, \"LayerZeroPacket: invalid packet\");\n\n        Buffer.buffer memory srcAddressBuffer;\n        srcAddressBuffer.init(sizeOfSrcAddress);\n        srcAddressBuffer.writeRawBytes(0, data, 42, sizeOfSrcAddress);\n\n        Buffer.buffer memory payloadBuffer;\n        if (payloadSize \u003e 0) {\n            payloadBuffer.init(payloadSize);\n            payloadBuffer.writeRawBytes(0, data, nonPayloadSize.add(32), payloadSize);\n        }\n\n        return LayerZeroPacket.Packet(srcChain, dstChain, nonce, dstAddress, srcAddressBuffer.buf, ulnAddress, payloadBuffer.buf);\n    }\n}\n"},"NonceContract.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity 0.7.6;\n\nimport \"./ILayerZeroEndpoint.sol\";\n\ncontract NonceContract {\n    ILayerZeroEndpoint public immutable endpoint;\n    // outboundNonce = [dstChainId][remoteAddress + localAddress]\n    mapping(uint16 =\u003e mapping(bytes =\u003e uint64)) public outboundNonce;\n\n    constructor(address _endpoint) {\n        endpoint = ILayerZeroEndpoint(_endpoint);\n    }\n\n    function increment(uint16 _chainId, address _ua, bytes calldata _path) external returns (uint64) {\n        require(endpoint.getSendLibraryAddress(_ua) == msg.sender, \"NonceContract: msg.sender is not valid sendlibrary\");\n        return ++outboundNonce[_chainId][_path];\n    }\n}\n"},"Ownable.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\nimport \"./Context.sol\";\n/**\n * @dev Contract module which provides a basic access control mechanism, where\n * there is an account (an owner) that can be granted exclusive access to\n * specific functions.\n *\n * By default, the owner account will be the one that deploys the contract. This\n * can later be changed with {transferOwnership}.\n *\n * This module is used through inheritance. It will make available the modifier\n * `onlyOwner`, which can be applied to your functions to restrict their use to\n * the owner.\n */\nabstract contract Ownable is Context {\n    address private _owner;\n\n    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);\n\n    /**\n     * @dev Initializes the contract setting the deployer as the initial owner.\n     */\n    constructor () {\n        address msgSender = _msgSender();\n        _owner = msgSender;\n        emit OwnershipTransferred(address(0), msgSender);\n    }\n\n    /**\n     * @dev Returns the address of the current owner.\n     */\n    function owner() public view virtual returns (address) {\n        return _owner;\n    }\n\n    /**\n     * @dev Throws if called by any account other than the owner.\n     */\n    modifier onlyOwner() {\n        require(owner() == _msgSender(), \"Ownable: caller is not the owner\");\n        _;\n    }\n\n    /**\n     * @dev Leaves the contract without owner. It will not be possible to call\n     * `onlyOwner` functions anymore. Can only be called by the current owner.\n     *\n     * NOTE: Renouncing ownership will leave the contract without an owner,\n     * thereby removing any functionality that is only available to the owner.\n     */\n    function renounceOwnership() public virtual onlyOwner {\n        emit OwnershipTransferred(_owner, address(0));\n        _owner = address(0);\n    }\n\n    /**\n     * @dev Transfers ownership of the contract to a new account (`newOwner`).\n     * Can only be called by the current owner.\n     */\n    function transferOwnership(address newOwner) public virtual onlyOwner {\n        require(newOwner != address(0), \"Ownable: new owner is the zero address\");\n        emit OwnershipTransferred(_owner, newOwner);\n        _owner = newOwner;\n    }\n}\n"},"ReentrancyGuard.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Contract module that helps prevent reentrant calls to a function.\n *\n * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier\n * available, which can be applied to functions to make sure there are no nested\n * (reentrant) calls to them.\n *\n * Note that because there is a single `nonReentrant` guard, functions marked as\n * `nonReentrant` may not call one another. This can be worked around by making\n * those functions `private`, and then adding `external` `nonReentrant` entry\n * points to them.\n *\n * TIP: If you would like to learn more about reentrancy and alternative ways\n * to protect against it, check out our blog post\n * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].\n */\nabstract contract ReentrancyGuard {\n    // Booleans are more expensive than uint256 or any type that takes up a full\n    // word because each write operation emits an extra SLOAD to first read the\n    // slot\u0027s contents, replace the bits taken up by the boolean, and then write\n    // back. This is the compiler\u0027s defense against contract upgrades and\n    // pointer aliasing, and it cannot be disabled.\n\n    // The values being non-zero value makes deployment a bit more expensive,\n    // but in exchange the refund on every call to nonReentrant will be lower in\n    // amount. Since refunds are capped to a percentage of the total\n    // transaction\u0027s gas, it is best to keep them low in cases like this one, to\n    // increase the likelihood of the full refund coming into effect.\n    uint256 private constant _NOT_ENTERED = 1;\n    uint256 private constant _ENTERED = 2;\n\n    uint256 private _status;\n\n    constructor () {\n        _status = _NOT_ENTERED;\n    }\n\n    /**\n     * @dev Prevents a contract from calling itself, directly or indirectly.\n     * Calling a `nonReentrant` function from another `nonReentrant`\n     * function is not supported. It is possible to prevent this from happening\n     * by making the `nonReentrant` function external, and make it call a\n     * `private` function that does the actual work.\n     */\n    modifier nonReentrant() {\n        // On the first call to nonReentrant, _notEntered will be true\n        require(_status != _ENTERED, \"ReentrancyGuard: reentrant call\");\n\n        // Any calls to nonReentrant after this point will fail\n        _status = _ENTERED;\n\n        _;\n\n        // By storing the original value once again, a refund is triggered (see\n        // https://eips.ethereum.org/EIPS/eip-2200)\n        _status = _NOT_ENTERED;\n    }\n}\n"},"SafeERC20.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\nimport \"./IERC20.sol\";\nimport \"./SafeMath.sol\";\nimport \"./Address.sol\";\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n    using SafeMath for uint256;\n    using Address for address;\n\n    function safeTransfer(IERC20 token, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n    }\n\n    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n    }\n\n    /**\n     * @dev Deprecated. This function has issues similar to the ones found in\n     * {IERC20-approve}, and its usage is discouraged.\n     *\n     * Whenever possible, use {safeIncreaseAllowance} and\n     * {safeDecreaseAllowance} instead.\n     */\n    function safeApprove(IERC20 token, address spender, uint256 value) internal {\n        // safeApprove should only be called when setting an initial allowance,\n        // or when resetting it to zero. To increase and decrease it, use\n        // \u0027safeIncreaseAllowance\u0027 and \u0027safeDecreaseAllowance\u0027\n        // solhint-disable-next-line max-line-length\n        require((value == 0) || (token.allowance(address(this), spender) == 0),\n            \"SafeERC20: approve from non-zero to non-zero allowance\"\n        );\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n    }\n\n    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).add(value);\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).sub(value, \"SafeERC20: decreased allowance below zero\");\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    /**\n     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n     * on the return value: the return value is optional (but if data is returned, it must not be false).\n     * @param token The token targeted by the call.\n     * @param data The call data (encoded using abi.encode or one of its variants).\n     */\n    function _callOptionalReturn(IERC20 token, bytes memory data) private {\n        // We need to perform a low level call here, to bypass Solidity\u0027s return data size checking mechanism, since\n        // we\u0027re implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that\n        // the target address contains contract code and also asserts for success in the low-level call.\n\n        bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n        if (returndata.length \u003e 0) { // Return data is optional\n            // solhint-disable-next-line max-line-length\n            require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n        }\n    }\n}\n"},"SafeMath.sol":{"content":"// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Wrappers over Solidity\u0027s arithmetic operations with added overflow\n * checks.\n *\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\n * in bugs, because programmers usually assume that an overflow raises an\n * error, which is the standard behavior in high level programming languages.\n * `SafeMath` restores this intuition by reverting the transaction when an\n * operation overflows.\n *\n * Using this library instead of the unchecked operations eliminates an entire\n * class of bugs, so it\u0027s recommended to use it always.\n */\nlibrary SafeMath {\n    /**\n     * @dev Returns the addition of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        uint256 c = a + b;\n        if (c \u003c a) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the substraction of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b \u003e a) return (false, 0);\n        return (true, a - b);\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        // Gas optimization: this is cheaper than requiring \u0027a\u0027 not being zero, but the\n        // benefit is lost if \u0027b\u0027 is also tested.\n        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n        if (a == 0) return (true, 0);\n        uint256 c = a * b;\n        if (c / a != b) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the division of two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a / b);\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a % b);\n    }\n\n    /**\n     * @dev Returns the addition of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity\u0027s `+` operator.\n     *\n     * Requirements:\n     *\n     * - Addition cannot overflow.\n     */\n    function add(uint256 a, uint256 b) internal pure returns (uint256) {\n        uint256 c = a + b;\n        require(c \u003e= a, \"SafeMath: addition overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting on\n     * overflow (when the result is negative).\n     *\n     * Counterpart to Solidity\u0027s `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003c= a, \"SafeMath: subtraction overflow\");\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity\u0027s `*` operator.\n     *\n     * Requirements:\n     *\n     * - Multiplication cannot overflow.\n     */\n    function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n        if (a == 0) return 0;\n        uint256 c = a * b;\n        require(c / a == b, \"SafeMath: multiplication overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting on\n     * division by zero. The result is rounded towards zero.\n     *\n     * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003e 0, \"SafeMath: division by zero\");\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting when dividing by zero.\n     *\n     * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b \u003e 0, \"SafeMath: modulo by zero\");\n        return a % b;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n     * overflow (when the result is negative).\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {trySub}.\n     *\n     * Counterpart to Solidity\u0027s `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003c= a, errorMessage);\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting with custom message on\n     * division by zero. The result is rounded towards zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryDiv}.\n     *\n     * Counterpart to Solidity\u0027s `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003e 0, errorMessage);\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting with custom message when dividing by zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryMod}.\n     *\n     * Counterpart to Solidity\u0027s `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b \u003e 0, errorMessage);\n        return a % b;\n    }\n}\n"},"UltraLightNodeV2.sol":{"content":"// SPDX-License-Identifier: BUSL-1.1\n\npragma solidity 0.7.6;\npragma abicoder v2;\n\nimport \"./Ownable.sol\";\nimport \"./SafeMath.sol\";\nimport \"./ReentrancyGuard.sol\";\nimport \"./IERC20.sol\";\nimport \"./SafeERC20.sol\";\n\nimport \"./ILayerZeroValidationLibrary.sol\";\nimport \"./ILayerZeroReceiver.sol\";\nimport \"./ILayerZeroTreasury.sol\";\nimport \"./ILayerZeroEndpoint.sol\";\n// v2\nimport \"./ILayerZeroMessagingLibraryV2.sol\";\nimport \"./ILayerZeroOracleV2.sol\";\nimport \"./ILayerZeroUltraLightNodeV2.sol\";\nimport \"./ILayerZeroRelayerV2.sol\";\nimport \"./NonceContract.sol\";\n\ncontract UltraLightNodeV2 is ILayerZeroMessagingLibraryV2, ILayerZeroUltraLightNodeV2, ReentrancyGuard, Ownable {\n    using SafeERC20 for IERC20;\n    using SafeMath for uint;\n\n    // Application config\n    uint public constant CONFIG_TYPE_INBOUND_PROOF_LIBRARY_VERSION = 1;\n    uint public constant CONFIG_TYPE_INBOUND_BLOCK_CONFIRMATIONS = 2;\n    uint public constant CONFIG_TYPE_RELAYER = 3;\n    uint public constant CONFIG_TYPE_OUTBOUND_PROOF_TYPE = 4;\n    uint public constant CONFIG_TYPE_OUTBOUND_BLOCK_CONFIRMATIONS = 5;\n    uint public constant CONFIG_TYPE_ORACLE = 6;\n\n    // Token and Contracts\n    IERC20 public layerZeroToken;\n    ILayerZeroTreasury public treasuryContract;\n\n    mapping(address =\u003e uint) public nativeFees;\n    uint public treasuryZROFees;\n\n    // User Application\n    mapping(address =\u003e mapping(uint16 =\u003e ApplicationConfiguration)) public appConfig; // app address =\u003e chainId =\u003e config\n    mapping(uint16 =\u003e ApplicationConfiguration) public defaultAppConfig; // default UA settings if no version specified\n    mapping(uint16 =\u003e mapping(uint16 =\u003e bytes)) public defaultAdapterParams;\n\n    // Validation\n    mapping(uint16 =\u003e mapping(uint16 =\u003e address)) public inboundProofLibrary; // chainId =\u003e library Id =\u003e inboundProofLibrary contract\n    mapping(uint16 =\u003e uint16) public maxInboundProofLibrary; // chainId =\u003e inboundProofLibrary\n    mapping(uint16 =\u003e mapping(uint16 =\u003e bool)) public supportedOutboundProof; // chainId =\u003e outboundProofType =\u003e enabled\n    mapping(uint16 =\u003e uint) public chainAddressSizeMap;\n    mapping(address =\u003e mapping(uint16 =\u003e mapping(bytes32 =\u003e mapping(bytes32 =\u003e uint)))) public hashLookup; //[oracle][srcChainId][blockhash][datahash] -\u003e confirmation\n    mapping(uint16 =\u003e bytes32) public ulnLookup; // remote ulns\n\n    ILayerZeroEndpoint public immutable endpoint;\n    uint16 public immutable localChainId;\n    NonceContract public immutable nonceContract;\n\n    constructor(address _endpoint, address _nonceContract, uint16 _localChainId) {\n        require(_endpoint != address(0x0), \"LayerZero: endpoint cannot be zero address\");\n        require(_nonceContract != address(0x0), \"LayerZero: nonceContract cannot be zero address\");\n        ILayerZeroEndpoint lzEndpoint = ILayerZeroEndpoint(_endpoint);\n        localChainId = _localChainId;\n        endpoint = lzEndpoint;\n        nonceContract = NonceContract(_nonceContract);\n    }\n\n    // only the endpoint can call SEND() and setConfig()\n    modifier onlyEndpoint() {\n        require(address(endpoint) == msg.sender, \"LayerZero: only endpoint\");\n        _;\n    }\n\n    //----------------------------------------------------------------------------------\n    // PROTOCOL\n    function validateTransactionProof(uint16 _srcChainId, address _dstAddress, uint _gasLimit, bytes32 _lookupHash, bytes32 _blockData, bytes calldata _transactionProof) external override {\n        // retrieve UA\u0027s configuration using the _dstAddress from arguments.\n        ApplicationConfiguration memory uaConfig = _getAppConfig(_srcChainId, _dstAddress);\n\n        // assert that the caller == UA\u0027s relayer\n        require(uaConfig.relayer == msg.sender, \"LayerZero: invalid relayer\");\n\n        LayerZeroPacket.Packet memory _packet;\n        uint remoteAddressSize = chainAddressSizeMap[_srcChainId];\n        require(remoteAddressSize != 0, \"LayerZero: incorrect remote address size\");\n        {\n            // assert that the data submitted by UA\u0027s oracle have no fewer confirmations than UA\u0027s configuration\n            uint storedConfirmations = hashLookup[uaConfig.oracle][_srcChainId][_lookupHash][_blockData];\n            require(storedConfirmations \u003e 0 \u0026\u0026 storedConfirmations \u003e= uaConfig.inboundBlockConfirmations, \"LayerZero: not enough block confirmations\");\n\n            // decode\n            address inboundProofLib = inboundProofLibrary[_srcChainId][uaConfig.inboundProofLibraryVersion];\n            _packet = ILayerZeroValidationLibrary(inboundProofLib).validateProof(_blockData, _transactionProof, remoteAddressSize);\n        }\n\n        // packet content assertion\n        require(ulnLookup[_srcChainId] == _packet.ulnAddress \u0026\u0026 _packet.ulnAddress != bytes32(0), \"LayerZero: invalid _packet.ulnAddress\");\n        require(_packet.srcChainId == _srcChainId, \"LayerZero: invalid srcChain Id\");\n        // failsafe because the remoteAddress size being passed into validateProof trims the address this should not hit\n        require(_packet.srcAddress.length == remoteAddressSize, \"LayerZero: invalid srcAddress size\");\n        require(_packet.dstChainId == localChainId, \"LayerZero: invalid dstChain Id\");\n        require(_packet.dstAddress == _dstAddress, \"LayerZero: invalid dstAddress\");\n\n        // if the dst is not a contract, then emit and return early. This will break inbound nonces, but this particular\n        // path is already broken and wont ever be able to deliver anyways\n        if (!_isContract(_dstAddress)) {\n            emit InvalidDst(_packet.srcChainId, _packet.srcAddress, _packet.dstAddress, _packet.nonce, keccak256(_packet.payload));\n            return;\n        }\n\n        bytes memory pathData = abi.encodePacked(_packet.srcAddress, _packet.dstAddress);\n        emit PacketReceived(_packet.srcChainId, _packet.srcAddress, _packet.dstAddress, _packet.nonce, keccak256(_packet.payload));\n        endpoint.receivePayload(_srcChainId, pathData, _dstAddress, _packet.nonce, _gasLimit, _packet.payload);\n    }\n\n    function send(address _ua, uint64, uint16 _dstChainId, bytes calldata _path, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable override onlyEndpoint {\n        address ua = _ua;\n        uint16 dstChainId = _dstChainId;\n        require(ulnLookup[dstChainId] != bytes32(0), \"LayerZero: dstChainId does not exist\");\n\n        bytes memory dstAddress;\n        uint64 nonce;\n        // code block for solving \u0027Stack Too Deep\u0027\n        {\n            uint chainAddressSize = chainAddressSizeMap[dstChainId];\n            // path = remoteAddress + localAddress\n            require(chainAddressSize != 0 \u0026\u0026 _path.length == 20 + chainAddressSize, \"LayerZero: incorrect remote address size\");\n            address srcInPath;\n            bytes memory path = _path; // copy to memory\n            assembly {\n                srcInPath := mload(add(add(path, 20), chainAddressSize)) // chainAddressSize + 20\n            }\n            require(ua == srcInPath, \"LayerZero: wrong path data\");\n            dstAddress = _path[0:chainAddressSize];\n            nonce = nonceContract.increment(dstChainId, ua, path);\n        }\n\n        bytes memory payload = _payload;\n        ApplicationConfiguration memory uaConfig = _getAppConfig(dstChainId, ua);\n\n        // compute all the fees\n        uint relayerFee = _handleRelayer(dstChainId, uaConfig, ua, payload.length, _adapterParams);\n        uint oracleFee = _handleOracle(dstChainId, uaConfig, ua);\n        uint nativeProtocolFee = _handleProtocolFee(relayerFee, oracleFee, ua, _zroPaymentAddress);\n\n        // total native fee, does not include ZRO protocol fee\n        uint totalNativeFee = relayerFee.add(oracleFee).add(nativeProtocolFee);\n\n        // assert the user has attached enough native token for this address\n        require(totalNativeFee \u003c= msg.value, \"LayerZero: not enough native for fees\");\n        // refund if they send too much\n        uint amount = msg.value.sub(totalNativeFee);\n        if (amount \u003e 0) {\n            (bool success, ) = _refundAddress.call{value: amount}(\"\");\n            require(success, \"LayerZero: failed to refund\");\n        }\n\n        // emit the data packet\n        bytes memory encodedPayload = abi.encodePacked(nonce, localChainId, ua, dstChainId, dstAddress, payload);\n        emit Packet(encodedPayload);\n    }\n\n    function _handleRelayer(uint16 _dstChainId, ApplicationConfiguration memory _uaConfig, address _ua, uint _payloadSize, bytes memory _adapterParams) internal returns (uint relayerFee) {\n        if (_adapterParams.length == 0) {\n            _adapterParams = defaultAdapterParams[_dstChainId][_uaConfig.outboundProofType];\n        }\n        address relayerAddress = _uaConfig.relayer;\n        ILayerZeroRelayerV2 relayer = ILayerZeroRelayerV2(relayerAddress);\n        relayerFee = relayer.assignJob(_dstChainId, _uaConfig.outboundProofType, _ua, _payloadSize, _adapterParams);\n\n        _creditNativeFee(relayerAddress, relayerFee);\n\n        // emit the param events\n        emit RelayerParams(_adapterParams, _uaConfig.outboundProofType);\n    }\n\n    function _handleOracle(uint16 _dstChainId, ApplicationConfiguration memory _uaConfig, address _ua) internal returns (uint oracleFee) {\n        address oracleAddress = _uaConfig.oracle;\n        oracleFee = ILayerZeroOracleV2(oracleAddress).assignJob(_dstChainId, _uaConfig.outboundProofType, _uaConfig.outboundBlockConfirmations, _ua);\n\n        _creditNativeFee(oracleAddress, oracleFee);\n    }\n\n    function _handleProtocolFee(uint _relayerFee, uint _oracleFee, address _ua, address _zroPaymentAddress) internal returns (uint protocolNativeFee) {\n        // if no ZRO token or not specifying a payment address, pay in native token\n        bool payInNative = _zroPaymentAddress == address(0x0) || address(layerZeroToken) == address(0x0);\n        uint protocolFee = treasuryContract.getFees(!payInNative, _relayerFee, _oracleFee);\n\n        if (protocolFee \u003e 0) {\n            if (payInNative) {\n                address treasuryAddress = address(treasuryContract);\n                _creditNativeFee(treasuryAddress, protocolFee);\n                protocolNativeFee = protocolFee;\n            } else {\n                // zro payment address must equal the ua or the tx.origin otherwise the transaction reverts\n                require(_zroPaymentAddress == _ua || _zroPaymentAddress == tx.origin, \"LayerZero: must be paid by sender or origin\");\n\n                // transfer the LayerZero token to this contract from the payee\n                layerZeroToken.safeTransferFrom(_zroPaymentAddress, address(this), protocolFee);\n\n                treasuryZROFees = treasuryZROFees.add(protocolFee);\n            }\n        }\n    }\n\n    function _creditNativeFee(address _receiver, uint _amount) internal {\n        nativeFees[_receiver] = nativeFees[_receiver].add(_amount);\n    }\n\n    // Can be called by any address to update a block header\n    // can only upload new block data or the same block data with more confirmations\n    function updateHash(uint16 _srcChainId, bytes32 _lookupHash, uint _confirmations, bytes32 _blockData) external override {\n        uint storedConfirmations = hashLookup[msg.sender][_srcChainId][_lookupHash][_blockData];\n\n        // if it has a record, requires a larger confirmation.\n        require(storedConfirmations \u003c _confirmations, \"LayerZero: oracle data can only update if it has more confirmations\");\n\n        // set the new information into storage\n        hashLookup[msg.sender][_srcChainId][_lookupHash][_blockData] = _confirmations;\n\n        emit HashReceived(_srcChainId, msg.sender, _lookupHash, _blockData, _confirmations);\n    }\n\n    //----------------------------------------------------------------------------------\n    // Other Library Interfaces\n\n    // default to DEFAULT setting if ZERO value\n    function getAppConfig(uint16 _remoteChainId, address _ua) external view override returns (ApplicationConfiguration memory) {\n        return _getAppConfig(_remoteChainId, _ua);\n    }\n\n    function _getAppConfig(uint16 _remoteChainId, address _ua) internal view returns (ApplicationConfiguration memory) {\n        ApplicationConfiguration memory config = appConfig[_ua][_remoteChainId];\n        ApplicationConfiguration storage defaultConfig = defaultAppConfig[_remoteChainId];\n\n        if (config.inboundProofLibraryVersion == 0) {\n            config.inboundProofLibraryVersion = defaultConfig.inboundProofLibraryVersion;\n        }\n\n        if (config.inboundBlockConfirmations == 0) {\n            config.inboundBlockConfirmations = defaultConfig.inboundBlockConfirmations;\n        }\n\n        if (config.relayer == address(0x0)) {\n            config.relayer = defaultConfig.relayer;\n        }\n\n        if (config.outboundProofType == 0) {\n            config.outboundProofType = defaultConfig.outboundProofType;\n        }\n\n        if (config.outboundBlockConfirmations == 0) {\n            config.outboundBlockConfirmations = defaultConfig.outboundBlockConfirmations;\n        }\n\n        if (config.oracle == address(0x0)) {\n            config.oracle = defaultConfig.oracle;\n        }\n\n        return config;\n    }\n\n    function setConfig(uint16 _remoteChainId, address _ua, uint _configType, bytes calldata _config) external override onlyEndpoint {\n        ApplicationConfiguration storage uaConfig = appConfig[_ua][_remoteChainId];\n        if (_configType == CONFIG_TYPE_INBOUND_PROOF_LIBRARY_VERSION) {\n            uint16 inboundProofLibraryVersion = abi.decode(_config, (uint16));\n            require(inboundProofLibraryVersion \u003c= maxInboundProofLibrary[_remoteChainId], \"LayerZero: invalid inbound proof library version\");\n            uaConfig.inboundProofLibraryVersion = inboundProofLibraryVersion;\n        } else if (_configType == CONFIG_TYPE_INBOUND_BLOCK_CONFIRMATIONS) {\n            uint64 blockConfirmations = abi.decode(_config, (uint64));\n            uaConfig.inboundBlockConfirmations = blockConfirmations;\n        } else if (_configType == CONFIG_TYPE_RELAYER) {\n            address relayer = abi.decode(_config, (address));\n            uaConfig.relayer = relayer;\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_PROOF_TYPE) {\n            uint16 outboundProofType = abi.decode(_config, (uint16));\n            require(supportedOutboundProof[_remoteChainId][outboundProofType] || outboundProofType == 0, \"LayerZero: invalid outbound proof type\");\n            uaConfig.outboundProofType = outboundProofType;\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_BLOCK_CONFIRMATIONS) {\n            uint64 blockConfirmations = abi.decode(_config, (uint64));\n            uaConfig.outboundBlockConfirmations = blockConfirmations;\n        } else if (_configType == CONFIG_TYPE_ORACLE) {\n            address oracle = abi.decode(_config, (address));\n            uaConfig.oracle = oracle;\n        } else {\n            revert(\"LayerZero: Invalid config type\");\n        }\n\n        emit AppConfigUpdated(_ua, _configType, _config);\n    }\n\n    function getConfig(uint16 _remoteChainId, address _ua, uint _configType) external view override returns (bytes memory) {\n        ApplicationConfiguration storage uaConfig = appConfig[_ua][_remoteChainId];\n\n        if (_configType == CONFIG_TYPE_INBOUND_PROOF_LIBRARY_VERSION) {\n            if (uaConfig.inboundProofLibraryVersion == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].inboundProofLibraryVersion);\n            }\n            return abi.encode(uaConfig.inboundProofLibraryVersion);\n        } else if (_configType == CONFIG_TYPE_INBOUND_BLOCK_CONFIRMATIONS) {\n            if (uaConfig.inboundBlockConfirmations == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].inboundBlockConfirmations);\n            }\n            return abi.encode(uaConfig.inboundBlockConfirmations);\n        } else if (_configType == CONFIG_TYPE_RELAYER) {\n            if (uaConfig.relayer == address(0x0)) {\n                return abi.encode(defaultAppConfig[_remoteChainId].relayer);\n            }\n            return abi.encode(uaConfig.relayer);\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_PROOF_TYPE) {\n            if (uaConfig.outboundProofType == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].outboundProofType);\n            }\n            return abi.encode(uaConfig.outboundProofType);\n        } else if (_configType == CONFIG_TYPE_OUTBOUND_BLOCK_CONFIRMATIONS) {\n            if (uaConfig.outboundBlockConfirmations == 0) {\n                return abi.encode(defaultAppConfig[_remoteChainId].outboundBlockConfirmations);\n            }\n            return abi.encode(uaConfig.outboundBlockConfirmations);\n        } else if (_configType == CONFIG_TYPE_ORACLE) {\n            if (uaConfig.oracle == address(0x0)) {\n                return abi.encode(defaultAppConfig[_remoteChainId].oracle);\n            }\n            return abi.encode(uaConfig.oracle);\n        } else {\n            revert(\"LayerZero: Invalid config type\");\n        }\n    }\n\n    // returns the native fee the UA pays to cover fees\n    function estimateFees(uint16 _dstChainId, address _ua, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParams) external view override returns (uint nativeFee, uint zroFee) {\n        ApplicationConfiguration memory uaConfig = _getAppConfig(_dstChainId, _ua);\n\n        // Relayer Fee\n        bytes memory adapterParams;\n        if (_adapterParams.length \u003e 0) {\n            adapterParams = _adapterParams;\n        } else {\n            adapterParams = defaultAdapterParams[_dstChainId][uaConfig.outboundProofType];\n        }\n        uint relayerFee = ILayerZeroRelayerV2(uaConfig.relayer).getFee(_dstChainId, uaConfig.outboundProofType, _ua, _payload.length, adapterParams);\n\n        // Oracle Fee\n        address ua = _ua; // stack too deep\n        uint oracleFee = ILayerZeroOracleV2(uaConfig.oracle).getFee(_dstChainId, uaConfig.outboundProofType, uaConfig.outboundBlockConfirmations, ua);\n\n        // LayerZero Fee\n        uint protocolFee = treasuryContract.getFees(_payInZRO, relayerFee, oracleFee);\n        _payInZRO ? zroFee = protocolFee : nativeFee = protocolFee;\n\n        // return the sum of fees\n        nativeFee = nativeFee.add(relayerFee).add(oracleFee);\n    }\n\n    //---------------------------------------------------------------------------\n    // Claim Fees\n\n    // universal withdraw ZRO token function\n    function withdrawZRO(address _to, uint _amount) external override nonReentrant {\n        require(msg.sender == address(treasuryContract), \"LayerZero: only treasury\");\n        treasuryZROFees = treasuryZROFees.sub(_amount);\n        layerZeroToken.safeTransfer(_to, _amount);\n        emit WithdrawZRO(msg.sender, _to, _amount);\n    }\n\n    // universal withdraw native token function.\n    // the source contract should perform all the authentication control\n    function withdrawNative(address payable _to, uint _amount) external override nonReentrant {\n        require(_to != address(0x0), \"LayerZero: _to cannot be zero address\");\n        nativeFees[msg.sender] = nativeFees[msg.sender].sub(_amount);\n\n        (bool success, ) = _to.call{value: _amount}(\"\");\n        require(success, \"LayerZero: withdraw failed\");\n        emit WithdrawNative(msg.sender, _to, _amount);\n    }\n\n    //---------------------------------------------------------------------------\n    // Owner calls, configuration only.\n    function setLayerZeroToken(address _layerZeroToken) external onlyOwner {\n        require(_layerZeroToken != address(0x0), \"LayerZero: _layerZeroToken cannot be zero address\");\n        layerZeroToken = IERC20(_layerZeroToken);\n        emit SetLayerZeroToken(_layerZeroToken);\n    }\n\n    function setTreasury(address _treasury) external onlyOwner {\n        require(_treasury != address(0x0), \"LayerZero: treasury cannot be zero address\");\n        treasuryContract = ILayerZeroTreasury(_treasury);\n        emit SetTreasury(_treasury);\n    }\n\n    function addInboundProofLibraryForChain(uint16 _chainId, address _library) external onlyOwner {\n        require(_library != address(0x0), \"LayerZero: library cannot be zero address\");\n        uint16 libId = maxInboundProofLibrary[_chainId];\n        require(libId \u003c 65535, \"LayerZero: can not add new library\");\n        maxInboundProofLibrary[_chainId] = ++libId;\n        inboundProofLibrary[_chainId][libId] = _library;\n        emit AddInboundProofLibraryForChain(_chainId, _library);\n    }\n\n    function enableSupportedOutboundProof(uint16 _chainId, uint16 _proofType) external onlyOwner {\n        supportedOutboundProof[_chainId][_proofType] = true;\n        emit EnableSupportedOutboundProof(_chainId, _proofType);\n    }\n\n    function setDefaultConfigForChainId(uint16 _chainId, uint16 _inboundProofLibraryVersion, uint64 _inboundBlockConfirmations, address _relayer, uint16 _outboundProofType, uint64 _outboundBlockConfirmations, address _oracle) external onlyOwner {\n        require(_inboundProofLibraryVersion \u003c= maxInboundProofLibrary[_chainId] \u0026\u0026 _inboundProofLibraryVersion \u003e 0, \"LayerZero: invalid inbound proof library version\");\n        require(_inboundBlockConfirmations \u003e 0, \"LayerZero: invalid inbound block confirmation\");\n        require(_relayer != address(0x0), \"LayerZero: invalid relayer address\");\n        require(supportedOutboundProof[_chainId][_outboundProofType], \"LayerZero: invalid outbound proof type\");\n        require(_outboundBlockConfirmations \u003e 0, \"LayerZero: invalid outbound block confirmation\");\n        require(_oracle != address(0x0), \"LayerZero: invalid oracle address\");\n        defaultAppConfig[_chainId] = ApplicationConfiguration(_inboundProofLibraryVersion, _inboundBlockConfirmations, _relayer, _outboundProofType, _outboundBlockConfirmations, _oracle);\n        emit SetDefaultConfigForChainId(_chainId, _inboundProofLibraryVersion, _inboundBlockConfirmations, _relayer, _outboundProofType, _outboundBlockConfirmations, _oracle);\n    }\n\n    function setDefaultAdapterParamsForChainId(uint16 _chainId, uint16 _proofType, bytes calldata _adapterParams) external onlyOwner {\n        defaultAdapterParams[_chainId][_proofType] = _adapterParams;\n        emit SetDefaultAdapterParamsForChainId(_chainId, _proofType, _adapterParams);\n    }\n\n    function setRemoteUln(uint16 _remoteChainId, bytes32 _remoteUln) external onlyOwner {\n        require(ulnLookup[_remoteChainId] == bytes32(0), \"LayerZero: remote uln already set\");\n        ulnLookup[_remoteChainId] = _remoteUln;\n        emit SetRemoteUln(_remoteChainId, _remoteUln);\n    }\n\n    function setChainAddressSize(uint16 _chainId, uint _size) external onlyOwner {\n        require(chainAddressSizeMap[_chainId] == 0, \"LayerZero: remote chain address size already set\");\n        chainAddressSizeMap[_chainId] = _size;\n        emit SetChainAddressSize(_chainId, _size);\n    }\n\n    //----------------------------------------------------------------------------------\n    // view functions\n\n    function accruedNativeFee(address _address) external view override returns (uint) {\n        return nativeFees[_address];\n    }\n\n    function getOutboundNonce(uint16 _chainId, bytes calldata _path) external view override returns (uint64) {\n        return nonceContract.outboundNonce(_chainId, _path);\n    }\n\n    function _isContract(address addr) internal view returns (bool) {\n        uint size;\n        assembly {\n            size := extcodesize(addr)\n        }\n        return size != 0;\n    }\n}\n"}}

                        File 8 of 12: NonceContract
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity 0.7.6;
                        import "./interfaces/ILayerZeroEndpoint.sol";
                        contract NonceContract {
                            ILayerZeroEndpoint public immutable endpoint;
                            // outboundNonce = [dstChainId][remoteAddress + localAddress]
                            mapping(uint16 => mapping(bytes => uint64)) public outboundNonce;
                            constructor(address _endpoint) {
                                endpoint = ILayerZeroEndpoint(_endpoint);
                            }
                            function increment(uint16 _chainId, address _ua, bytes calldata _path) external returns (uint64) {
                                require(endpoint.getSendLibraryAddress(_ua) == msg.sender, "NonceContract: msg.sender is not valid sendlibrary");
                                return ++outboundNonce[_chainId][_path];
                            }
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.5.0;
                        import "./ILayerZeroUserApplicationConfig.sol";
                        interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
                            // @notice send a LayerZero message to the specified address at a LayerZero endpoint.
                            // @param _dstChainId - the destination chain identifier
                            // @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
                            // @param _payload - a custom bytes payload to send to the destination contract
                            // @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
                            // @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
                            // @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
                            function send(uint16 _dstChainId, bytes calldata _destination, bytes calldata _payload, address payable _refundAddress, address _zroPaymentAddress, bytes calldata _adapterParams) external payable;
                            // @notice used by the messaging library to publish verified payload
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source contract (as bytes) at the source chain
                            // @param _dstAddress - the address on destination chain
                            // @param _nonce - the unbound message ordering nonce
                            // @param _gasLimit - the gas limit for external contract execution
                            // @param _payload - verified payload to send to the destination contract
                            function receivePayload(uint16 _srcChainId, bytes calldata _srcAddress, address _dstAddress, uint64 _nonce, uint _gasLimit, bytes calldata _payload) external;
                            // @notice get the inboundNonce of a receiver from a source chain which could be EVM or non-EVM chain
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
                            // @notice get the outboundNonce from this source chain which, consequently, is always an EVM
                            // @param _srcAddress - the source chain contract address
                            function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
                            // @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
                            // @param _dstChainId - the destination chain identifier
                            // @param _userApplication - the user app address on this EVM chain
                            // @param _payload - the custom message to send over LayerZero
                            // @param _payInZRO - if false, user app pays the protocol fee in native token
                            // @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
                            function estimateFees(uint16 _dstChainId, address _userApplication, bytes calldata _payload, bool _payInZRO, bytes calldata _adapterParam) external view returns (uint nativeFee, uint zroFee);
                            // @notice get this Endpoint's immutable source identifier
                            function getChainId() external view returns (uint16);
                            // @notice the interface to retry failed message on this Endpoint destination
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            // @param _payload - the payload to be retried
                            function retryPayload(uint16 _srcChainId, bytes calldata _srcAddress, bytes calldata _payload) external;
                            // @notice query if any STORED payload (message blocking) at the endpoint.
                            // @param _srcChainId - the source chain identifier
                            // @param _srcAddress - the source chain contract address
                            function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
                            // @notice query if the _libraryAddress is valid for sending msgs.
                            // @param _userApplication - the user app address on this EVM chain
                            function getSendLibraryAddress(address _userApplication) external view returns (address);
                            // @notice query if the _libraryAddress is valid for receiving msgs.
                            // @param _userApplication - the user app address on this EVM chain
                            function getReceiveLibraryAddress(address _userApplication) external view returns (address);
                            // @notice query if the non-reentrancy guard for send() is on
                            // @return true if the guard is on. false otherwise
                            function isSendingPayload() external view returns (bool);
                            // @notice query if the non-reentrancy guard for receive() is on
                            // @return true if the guard is on. false otherwise
                            function isReceivingPayload() external view returns (bool);
                            // @notice get the configuration of the LayerZero messaging library of the specified version
                            // @param _version - messaging library version
                            // @param _chainId - the chainId for the pending config change
                            // @param _userApplication - the contract address of the user application
                            // @param _configType - type of configuration. every messaging library has its own convention.
                            function getConfig(uint16 _version, uint16 _chainId, address _userApplication, uint _configType) external view returns (bytes memory);
                            // @notice get the send() LayerZero messaging library version
                            // @param _userApplication - the contract address of the user application
                            function getSendVersion(address _userApplication) external view returns (uint16);
                            // @notice get the lzReceive() LayerZero messaging library version
                            // @param _userApplication - the contract address of the user application
                            function getReceiveVersion(address _userApplication) external view returns (uint16);
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.5.0;
                        interface ILayerZeroUserApplicationConfig {
                            // @notice set the configuration of the LayerZero messaging library of the specified version
                            // @param _version - messaging library version
                            // @param _chainId - the chainId for the pending config change
                            // @param _configType - type of configuration. every messaging library has its own convention.
                            // @param _config - configuration in the bytes. can encode arbitrary content.
                            function setConfig(uint16 _version, uint16 _chainId, uint _configType, bytes calldata _config) external;
                            // @notice set the send() LayerZero messaging library version to _version
                            // @param _version - new messaging library version
                            function setSendVersion(uint16 _version) external;
                            // @notice set the lzReceive() LayerZero messaging library version to _version
                            // @param _version - new messaging library version
                            function setReceiveVersion(uint16 _version) external;
                            // @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
                            // @param _srcChainId - the chainId of the source chain
                            // @param _srcAddress - the contract address of the source contract at the source chain
                            function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
                        }
                        

                        File 9 of 12: OptimizedTransparentUpgradeableProxy
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        /**
                         * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
                         * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
                         * be specified by overriding the virtual {_implementation} function.
                         * 
                         * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
                         * different contract through the {_delegate} function.
                         * 
                         * The success and return data of the delegated call will be returned back to the caller of the proxy.
                         */
                        abstract contract Proxy {
                            /**
                             * @dev Delegates the current call to `implementation`.
                             * 
                             * This function does not return to its internall call site, it will return directly to the external caller.
                             */
                            function _delegate(address implementation) internal {
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    // Copy msg.data. We take full control of memory in this inline assembly
                                    // block because it will not return to Solidity code. We overwrite the
                                    // Solidity scratch pad at memory position 0.
                                    calldatacopy(0, 0, calldatasize())
                                    // Call the implementation.
                                    // out and outsize are 0 because we don't know the size yet.
                                    let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                                    // Copy the returned data.
                                    returndatacopy(0, 0, returndatasize())
                                    switch result
                                    // delegatecall returns 0 on error.
                                    case 0 { revert(0, returndatasize()) }
                                    default { return(0, returndatasize()) }
                                }
                            }
                            /**
                             * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                             * and {_fallback} should delegate.
                             */
                            function _implementation() internal virtual view returns (address);
                            /**
                             * @dev Delegates the current call to the address returned by `_implementation()`.
                             * 
                             * This function does not return to its internall call site, it will return directly to the external caller.
                             */
                            function _fallback() internal {
                                _beforeFallback();
                                _delegate(_implementation());
                            }
                            /**
                             * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                             * function in the contract matches the call data.
                             */
                            fallback () payable external {
                                _fallback();
                            }
                            /**
                             * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                             * is empty.
                             */
                            receive () payable external {
                                _fallback();
                            }
                            /**
                             * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                             * call, or as part of the Solidity `fallback` or `receive` functions.
                             * 
                             * If overriden should call `super._beforeFallback()`.
                             */
                            function _beforeFallback() internal virtual {
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        import "./Proxy.sol";
                        import "../utils/Address.sol";
                        /**
                         * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
                         * implementation address that can be changed. This address is stored in storage in the location specified by
                         * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
                         * implementation behind the proxy.
                         * 
                         * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
                         * {TransparentUpgradeableProxy}.
                         */
                        contract UpgradeableProxy is Proxy {
                            /**
                             * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                             * 
                             * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                             * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                             */
                            constructor(address _logic, bytes memory _data) payable {
                                assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                                _setImplementation(_logic);
                                if(_data.length > 0) {
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success,) = _logic.delegatecall(_data);
                                    require(success);
                                }
                            }
                            /**
                             * @dev Emitted when the implementation is upgraded.
                             */
                            event Upgraded(address indexed implementation);
                            /**
                             * @dev Storage slot with the address of the current implementation.
                             * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                             * validated in the constructor.
                             */
                            bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                            /**
                             * @dev Returns the current implementation address.
                             */
                            function _implementation() internal override view returns (address impl) {
                                bytes32 slot = _IMPLEMENTATION_SLOT;
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    impl := sload(slot)
                                }
                            }
                            /**
                             * @dev Upgrades the proxy to a new implementation.
                             * 
                             * Emits an {Upgraded} event.
                             */
                            function _upgradeTo(address newImplementation) internal {
                                _setImplementation(newImplementation);
                                emit Upgraded(newImplementation);
                            }
                            /**
                             * @dev Stores a new address in the EIP1967 implementation slot.
                             */
                            function _setImplementation(address newImplementation) private {
                                require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
                                bytes32 slot = _IMPLEMENTATION_SLOT;
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    sstore(slot, newImplementation)
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        /**
                         * @dev Collection of functions related to the address type
                         */
                        library Address {
                            /**
                             * @dev Returns true if `account` is a contract.
                             *
                             * [IMPORTANT]
                             * ====
                             * It is unsafe to assume that an address for which this function returns
                             * false is an externally-owned account (EOA) and not a contract.
                             *
                             * Among others, `isContract` will return false for the following
                             * types of addresses:
                             *
                             *  - an externally-owned account
                             *  - a contract in construction
                             *  - an address where a contract will be created
                             *  - an address where a contract lived, but was destroyed
                             * ====
                             */
                            function isContract(address account) internal view returns (bool) {
                                // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
                                // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
                                // for accounts without code, i.e. `keccak256('')`
                                bytes32 codehash;
                                bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
                                // solhint-disable-next-line no-inline-assembly
                                assembly { codehash := extcodehash(account) }
                                return (codehash != accountHash && codehash != 0x0);
                            }
                            /**
                             * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                             * `recipient`, forwarding all available gas and reverting on errors.
                             *
                             * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                             * of certain opcodes, possibly making contracts go over the 2300 gas limit
                             * imposed by `transfer`, making them unable to receive funds via
                             * `transfer`. {sendValue} removes this limitation.
                             *
                             * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                             *
                             * IMPORTANT: because control is transferred to `recipient`, care must be
                             * taken to not create reentrancy vulnerabilities. Consider using
                             * {ReentrancyGuard} or the
                             * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                             */
                            function sendValue(address payable recipient, uint256 amount) internal {
                                require(address(this).balance >= amount, "Address: insufficient balance");
                                // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                                (bool success, ) = recipient.call{ value: amount }("");
                                require(success, "Address: unable to send value, recipient may have reverted");
                            }
                            /**
                             * @dev Performs a Solidity function call using a low level `call`. A
                             * plain`call` is an unsafe replacement for a function call: use this
                             * function instead.
                             *
                             * If `target` reverts with a revert reason, it is bubbled up by this
                             * function (like regular Solidity function calls).
                             *
                             * Returns the raw returned data. To convert to the expected return value,
                             * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                             *
                             * Requirements:
                             *
                             * - `target` must be a contract.
                             * - calling `target` with `data` must not revert.
                             *
                             * _Available since v3.1._
                             */
                            function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                              return functionCall(target, data, "Address: low-level call failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                             * `errorMessage` as a fallback revert reason when `target` reverts.
                             *
                             * _Available since v3.1._
                             */
                            function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                                return _functionCallWithValue(target, data, 0, errorMessage);
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                             * but also transferring `value` wei to `target`.
                             *
                             * Requirements:
                             *
                             * - the calling contract must have an ETH balance of at least `value`.
                             * - the called Solidity function must be `payable`.
                             *
                             * _Available since v3.1._
                             */
                            function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                                return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                             * with `errorMessage` as a fallback revert reason when `target` reverts.
                             *
                             * _Available since v3.1._
                             */
                            function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                                require(address(this).balance >= value, "Address: insufficient balance for call");
                                return _functionCallWithValue(target, data, value, errorMessage);
                            }
                            function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
                                require(isContract(target), "Address: call to non-contract");
                                // solhint-disable-next-line avoid-low-level-calls
                                (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
                                if (success) {
                                    return returndata;
                                } else {
                                    // Look for revert reason and bubble it up if present
                                    if (returndata.length > 0) {
                                        // The easiest way to bubble the revert reason is using memory via assembly
                                        // solhint-disable-next-line no-inline-assembly
                                        assembly {
                                            let returndata_size := mload(returndata)
                                            revert(add(32, returndata), returndata_size)
                                        }
                                    } else {
                                        revert(errorMessage);
                                    }
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        import "../openzeppelin/proxy/UpgradeableProxy.sol";
                        /**
                         * @dev This contract implements a proxy that is upgradeable by an admin.
                         *
                         * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
                         * clashing], which can potentially be used in an attack, this contract uses the
                         * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
                         * things that go hand in hand:
                         *
                         * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
                         * that call matches one of the admin functions exposed by the proxy itself.
                         * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
                         * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
                         * "admin cannot fallback to proxy target".
                         *
                         * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
                         * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
                         * to sudden errors when trying to call a function from the proxy implementation.
                         *
                         * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
                         * you should think of the `ProxyAdmin` instance as the real administrative inerface of your proxy.
                         */
                        contract OptimizedTransparentUpgradeableProxy is UpgradeableProxy {
                            address internal immutable _ADMIN;
                            /**
                             * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                             * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
                             */
                            constructor(
                                address initialLogic,
                                address initialAdmin,
                                bytes memory _data
                            ) payable UpgradeableProxy(initialLogic, _data) {
                                assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                                bytes32 slot = _ADMIN_SLOT;
                                _ADMIN = initialAdmin;
                                // still store it to work with EIP-1967
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    sstore(slot, initialAdmin)
                                }
                            }
                            /**
                             * @dev Storage slot with the admin of the contract.
                             * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                             * validated in the constructor.
                             */
                            bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                            /**
                             * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                             */
                            modifier ifAdmin() {
                                if (msg.sender == _admin()) {
                                    _;
                                } else {
                                    _fallback();
                                }
                            }
                            /**
                             * @dev Returns the current admin.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                             *
                             * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                             * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                             * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                             */
                            function admin() external ifAdmin returns (address) {
                                return _admin();
                            }
                            /**
                             * @dev Returns the current implementation.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                             *
                             * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                             * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                             * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                             */
                            function implementation() external ifAdmin returns (address) {
                                return _implementation();
                            }
                            /**
                             * @dev Upgrade the implementation of the proxy.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                             */
                            function upgradeTo(address newImplementation) external ifAdmin {
                                _upgradeTo(newImplementation);
                            }
                            /**
                             * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                             * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                             * proxied contract.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                             */
                            function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                                _upgradeTo(newImplementation);
                                // solhint-disable-next-line avoid-low-level-calls
                                (bool success, ) = newImplementation.delegatecall(data);
                                require(success);
                            }
                            /**
                             * @dev Returns the current admin.
                             */
                            function _admin() internal view returns (address adm) {
                                return _ADMIN;
                            }
                            /**
                             * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                             */
                            function _beforeFallback() internal virtual override {
                                require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                                super._beforeFallback();
                            }
                        }
                        

                        File 10 of 12: OptimizedTransparentUpgradeableProxy
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (interfaces/draft-IERC1822.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
                         * proxy whose upgrades are fully controlled by the current implementation.
                         */
                        interface IERC1822Proxiable {
                            /**
                             * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
                             * address.
                             *
                             * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
                             * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
                             * function revert if invoked through a proxy.
                             */
                            function proxiableUUID() external view returns (bytes32);
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (proxy/ERC1967/ERC1967Proxy.sol)
                        pragma solidity ^0.8.0;
                        import "../Proxy.sol";
                        import "./ERC1967Upgrade.sol";
                        /**
                         * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
                         * implementation address that can be changed. This address is stored in storage in the location specified by
                         * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
                         * implementation behind the proxy.
                         */
                        contract ERC1967Proxy is Proxy, ERC1967Upgrade {
                            /**
                             * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                             *
                             * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                             * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                             */
                            constructor(address _logic, bytes memory _data) payable {
                                assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                                _upgradeToAndCall(_logic, _data, false);
                            }
                            /**
                             * @dev Returns the current implementation address.
                             */
                            function _implementation() internal view virtual override returns (address impl) {
                                return ERC1967Upgrade._getImplementation();
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/ERC1967/ERC1967Upgrade.sol)
                        pragma solidity ^0.8.2;
                        import "../beacon/IBeacon.sol";
                        import "../../interfaces/draft-IERC1822.sol";
                        import "../../utils/Address.sol";
                        import "../../utils/StorageSlot.sol";
                        /**
                         * @dev This abstract contract provides getters and event emitting update functions for
                         * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
                         *
                         * _Available since v4.1._
                         *
                         * @custom:oz-upgrades-unsafe-allow delegatecall
                         */
                        abstract contract ERC1967Upgrade {
                            // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
                            bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
                            /**
                             * @dev Storage slot with the address of the current implementation.
                             * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                             * validated in the constructor.
                             */
                            bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                            /**
                             * @dev Emitted when the implementation is upgraded.
                             */
                            event Upgraded(address indexed implementation);
                            /**
                             * @dev Returns the current implementation address.
                             */
                            function _getImplementation() internal view returns (address) {
                                return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                            }
                            /**
                             * @dev Stores a new address in the EIP1967 implementation slot.
                             */
                            function _setImplementation(address newImplementation) private {
                                require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                                StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                            }
                            /**
                             * @dev Perform implementation upgrade
                             *
                             * Emits an {Upgraded} event.
                             */
                            function _upgradeTo(address newImplementation) internal {
                                _setImplementation(newImplementation);
                                emit Upgraded(newImplementation);
                            }
                            /**
                             * @dev Perform implementation upgrade with additional setup call.
                             *
                             * Emits an {Upgraded} event.
                             */
                            function _upgradeToAndCall(
                                address newImplementation,
                                bytes memory data,
                                bool forceCall
                            ) internal {
                                _upgradeTo(newImplementation);
                                if (data.length > 0 || forceCall) {
                                    Address.functionDelegateCall(newImplementation, data);
                                }
                            }
                            /**
                             * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
                             *
                             * Emits an {Upgraded} event.
                             */
                            function _upgradeToAndCallUUPS(
                                address newImplementation,
                                bytes memory data,
                                bool forceCall
                            ) internal {
                                // Upgrades from old implementations will perform a rollback test. This test requires the new
                                // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                                // this special case will break upgrade paths from old UUPS implementation to new ones.
                                if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
                                    _setImplementation(newImplementation);
                                } else {
                                    try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                                        require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                                    } catch {
                                        revert("ERC1967Upgrade: new implementation is not UUPS");
                                    }
                                    _upgradeToAndCall(newImplementation, data, forceCall);
                                }
                            }
                            /**
                             * @dev Storage slot with the admin of the contract.
                             * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                             * validated in the constructor.
                             */
                            bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                            /**
                             * @dev Emitted when the admin account has changed.
                             */
                            event AdminChanged(address previousAdmin, address newAdmin);
                            /**
                             * @dev Returns the current admin.
                             */
                            function _getAdmin() internal view virtual returns (address) {
                                return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
                            }
                            /**
                             * @dev Stores a new address in the EIP1967 admin slot.
                             */
                            function _setAdmin(address newAdmin) private {
                                require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                                StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
                            }
                            /**
                             * @dev Changes the admin of the proxy.
                             *
                             * Emits an {AdminChanged} event.
                             */
                            function _changeAdmin(address newAdmin) internal {
                                emit AdminChanged(_getAdmin(), newAdmin);
                                _setAdmin(newAdmin);
                            }
                            /**
                             * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
                             * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
                             */
                            bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
                            /**
                             * @dev Emitted when the beacon is upgraded.
                             */
                            event BeaconUpgraded(address indexed beacon);
                            /**
                             * @dev Returns the current beacon.
                             */
                            function _getBeacon() internal view returns (address) {
                                return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
                            }
                            /**
                             * @dev Stores a new beacon in the EIP1967 beacon slot.
                             */
                            function _setBeacon(address newBeacon) private {
                                require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                                require(Address.isContract(IBeacon(newBeacon).implementation()), "ERC1967: beacon implementation is not a contract");
                                StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
                            }
                            /**
                             * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
                             * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
                             *
                             * Emits a {BeaconUpgraded} event.
                             */
                            function _upgradeBeaconToAndCall(
                                address newBeacon,
                                bytes memory data,
                                bool forceCall
                            ) internal {
                                _setBeacon(newBeacon);
                                emit BeaconUpgraded(newBeacon);
                                if (data.length > 0 || forceCall) {
                                    Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/Proxy.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
                         * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
                         * be specified by overriding the virtual {_implementation} function.
                         *
                         * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
                         * different contract through the {_delegate} function.
                         *
                         * The success and return data of the delegated call will be returned back to the caller of the proxy.
                         */
                        abstract contract Proxy {
                            /**
                             * @dev Delegates the current call to `implementation`.
                             *
                             * This function does not return to its internal call site, it will return directly to the external caller.
                             */
                            function _delegate(address implementation) internal virtual {
                                assembly {
                                    // Copy msg.data. We take full control of memory in this inline assembly
                                    // block because it will not return to Solidity code. We overwrite the
                                    // Solidity scratch pad at memory position 0.
                                    calldatacopy(0, 0, calldatasize())
                                    // Call the implementation.
                                    // out and outsize are 0 because we don't know the size yet.
                                    let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                                    // Copy the returned data.
                                    returndatacopy(0, 0, returndatasize())
                                    switch result
                                    // delegatecall returns 0 on error.
                                    case 0 {
                                        revert(0, returndatasize())
                                    }
                                    default {
                                        return(0, returndatasize())
                                    }
                                }
                            }
                            /**
                             * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                             * and {_fallback} should delegate.
                             */
                            function _implementation() internal view virtual returns (address);
                            /**
                             * @dev Delegates the current call to the address returned by `_implementation()`.
                             *
                             * This function does not return to its internall call site, it will return directly to the external caller.
                             */
                            function _fallback() internal virtual {
                                _beforeFallback();
                                _delegate(_implementation());
                            }
                            /**
                             * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                             * function in the contract matches the call data.
                             */
                            fallback() external payable virtual {
                                _fallback();
                            }
                            /**
                             * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                             * is empty.
                             */
                            receive() external payable virtual {
                                _fallback();
                            }
                            /**
                             * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                             * call, or as part of the Solidity `fallback` or `receive` functions.
                             *
                             * If overriden should call `super._beforeFallback()`.
                             */
                            function _beforeFallback() internal virtual {}
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev This is the interface that {BeaconProxy} expects of its beacon.
                         */
                        interface IBeacon {
                            /**
                             * @dev Must return an address that can be used as a delegate call target.
                             *
                             * {BeaconProxy} will check that this address is a contract.
                             */
                            function implementation() external view returns (address);
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (utils/Address.sol)
                        pragma solidity ^0.8.1;
                        /**
                         * @dev Collection of functions related to the address type
                         */
                        library Address {
                            /**
                             * @dev Returns true if `account` is a contract.
                             *
                             * [IMPORTANT]
                             * ====
                             * It is unsafe to assume that an address for which this function returns
                             * false is an externally-owned account (EOA) and not a contract.
                             *
                             * Among others, `isContract` will return false for the following
                             * types of addresses:
                             *
                             *  - an externally-owned account
                             *  - a contract in construction
                             *  - an address where a contract will be created
                             *  - an address where a contract lived, but was destroyed
                             * ====
                             *
                             * [IMPORTANT]
                             * ====
                             * You shouldn't rely on `isContract` to protect against flash loan attacks!
                             *
                             * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                             * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                             * constructor.
                             * ====
                             */
                            function isContract(address account) internal view returns (bool) {
                                // This method relies on extcodesize/address.code.length, which returns 0
                                // for contracts in construction, since the code is only stored at the end
                                // of the constructor execution.
                                return account.code.length > 0;
                            }
                            /**
                             * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                             * `recipient`, forwarding all available gas and reverting on errors.
                             *
                             * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                             * of certain opcodes, possibly making contracts go over the 2300 gas limit
                             * imposed by `transfer`, making them unable to receive funds via
                             * `transfer`. {sendValue} removes this limitation.
                             *
                             * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                             *
                             * IMPORTANT: because control is transferred to `recipient`, care must be
                             * taken to not create reentrancy vulnerabilities. Consider using
                             * {ReentrancyGuard} or the
                             * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                             */
                            function sendValue(address payable recipient, uint256 amount) internal {
                                require(address(this).balance >= amount, "Address: insufficient balance");
                                (bool success, ) = recipient.call{value: amount}("");
                                require(success, "Address: unable to send value, recipient may have reverted");
                            }
                            /**
                             * @dev Performs a Solidity function call using a low level `call`. A
                             * plain `call` is an unsafe replacement for a function call: use this
                             * function instead.
                             *
                             * If `target` reverts with a revert reason, it is bubbled up by this
                             * function (like regular Solidity function calls).
                             *
                             * Returns the raw returned data. To convert to the expected return value,
                             * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                             *
                             * Requirements:
                             *
                             * - `target` must be a contract.
                             * - calling `target` with `data` must not revert.
                             *
                             * _Available since v3.1._
                             */
                            function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                                return functionCall(target, data, "Address: low-level call failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                             * `errorMessage` as a fallback revert reason when `target` reverts.
                             *
                             * _Available since v3.1._
                             */
                            function functionCall(
                                address target,
                                bytes memory data,
                                string memory errorMessage
                            ) internal returns (bytes memory) {
                                return functionCallWithValue(target, data, 0, errorMessage);
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                             * but also transferring `value` wei to `target`.
                             *
                             * Requirements:
                             *
                             * - the calling contract must have an ETH balance of at least `value`.
                             * - the called Solidity function must be `payable`.
                             *
                             * _Available since v3.1._
                             */
                            function functionCallWithValue(
                                address target,
                                bytes memory data,
                                uint256 value
                            ) internal returns (bytes memory) {
                                return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                             * with `errorMessage` as a fallback revert reason when `target` reverts.
                             *
                             * _Available since v3.1._
                             */
                            function functionCallWithValue(
                                address target,
                                bytes memory data,
                                uint256 value,
                                string memory errorMessage
                            ) internal returns (bytes memory) {
                                require(address(this).balance >= value, "Address: insufficient balance for call");
                                require(isContract(target), "Address: call to non-contract");
                                (bool success, bytes memory returndata) = target.call{value: value}(data);
                                return verifyCallResult(success, returndata, errorMessage);
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                             * but performing a static call.
                             *
                             * _Available since v3.3._
                             */
                            function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                                return functionStaticCall(target, data, "Address: low-level static call failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                             * but performing a static call.
                             *
                             * _Available since v3.3._
                             */
                            function functionStaticCall(
                                address target,
                                bytes memory data,
                                string memory errorMessage
                            ) internal view returns (bytes memory) {
                                require(isContract(target), "Address: static call to non-contract");
                                (bool success, bytes memory returndata) = target.staticcall(data);
                                return verifyCallResult(success, returndata, errorMessage);
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                             * but performing a delegate call.
                             *
                             * _Available since v3.4._
                             */
                            function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                                return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                             * but performing a delegate call.
                             *
                             * _Available since v3.4._
                             */
                            function functionDelegateCall(
                                address target,
                                bytes memory data,
                                string memory errorMessage
                            ) internal returns (bytes memory) {
                                require(isContract(target), "Address: delegate call to non-contract");
                                (bool success, bytes memory returndata) = target.delegatecall(data);
                                return verifyCallResult(success, returndata, errorMessage);
                            }
                            /**
                             * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                             * revert reason using the provided one.
                             *
                             * _Available since v4.3._
                             */
                            function verifyCallResult(
                                bool success,
                                bytes memory returndata,
                                string memory errorMessage
                            ) internal pure returns (bytes memory) {
                                if (success) {
                                    return returndata;
                                } else {
                                    // Look for revert reason and bubble it up if present
                                    if (returndata.length > 0) {
                                        // The easiest way to bubble the revert reason is using memory via assembly
                                        assembly {
                                            let returndata_size := mload(returndata)
                                            revert(add(32, returndata), returndata_size)
                                        }
                                    } else {
                                        revert(errorMessage);
                                    }
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (utils/StorageSlot.sol)
                        pragma solidity ^0.8.0;
                        /**
                         * @dev Library for reading and writing primitive types to specific storage slots.
                         *
                         * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
                         * This library helps with reading and writing to such slots without the need for inline assembly.
                         *
                         * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
                         *
                         * Example usage to set ERC1967 implementation slot:
                         * ```
                         * contract ERC1967 {
                         *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                         *
                         *     function _getImplementation() internal view returns (address) {
                         *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
                         *     }
                         *
                         *     function _setImplementation(address newImplementation) internal {
                         *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                         *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
                         *     }
                         * }
                         * ```
                         *
                         * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
                         */
                        library StorageSlot {
                            struct AddressSlot {
                                address value;
                            }
                            struct BooleanSlot {
                                bool value;
                            }
                            struct Bytes32Slot {
                                bytes32 value;
                            }
                            struct Uint256Slot {
                                uint256 value;
                            }
                            /**
                             * @dev Returns an `AddressSlot` with member `value` located at `slot`.
                             */
                            function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                                assembly {
                                    r.slot := slot
                                }
                            }
                            /**
                             * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
                             */
                            function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                                assembly {
                                    r.slot := slot
                                }
                            }
                            /**
                             * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
                             */
                            function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                                assembly {
                                    r.slot := slot
                                }
                            }
                            /**
                             * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
                             */
                            function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                                assembly {
                                    r.slot := slot
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        // OpenZeppelin Contracts v4.4.1 (proxy/transparent/TransparentUpgradeableProxy.sol)
                        pragma solidity ^0.8.0;
                        import "../openzeppelin/proxy/ERC1967/ERC1967Proxy.sol";
                        /**
                         * @dev This contract implements a proxy that is upgradeable by an admin.
                         *
                         * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
                         * clashing], which can potentially be used in an attack, this contract uses the
                         * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
                         * things that go hand in hand:
                         *
                         * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
                         * that call matches one of the admin functions exposed by the proxy itself.
                         * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
                         * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
                         * "admin cannot fallback to proxy target".
                         *
                         * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
                         * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
                         * to sudden errors when trying to call a function from the proxy implementation.
                         *
                         * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
                         * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
                         */
                        contract OptimizedTransparentUpgradeableProxy is ERC1967Proxy {
                            address internal immutable _ADMIN;
                            /**
                             * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                             * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
                             */
                            constructor(
                                address _logic,
                                address admin_,
                                bytes memory _data
                            ) payable ERC1967Proxy(_logic, _data) {
                                assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                                _ADMIN = admin_;
                                // still store it to work with EIP-1967
                                bytes32 slot = _ADMIN_SLOT;
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    sstore(slot, admin_)
                                }
                                emit AdminChanged(address(0), admin_);
                            }
                            /**
                             * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                             */
                            modifier ifAdmin() {
                                if (msg.sender == _getAdmin()) {
                                    _;
                                } else {
                                    _fallback();
                                }
                            }
                            /**
                             * @dev Returns the current admin.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                             *
                             * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                             * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                             * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                             */
                            function admin() external ifAdmin returns (address admin_) {
                                admin_ = _getAdmin();
                            }
                            /**
                             * @dev Returns the current implementation.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                             *
                             * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                             * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                             * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                             */
                            function implementation() external ifAdmin returns (address implementation_) {
                                implementation_ = _implementation();
                            }
                            /**
                             * @dev Upgrade the implementation of the proxy.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                             */
                            function upgradeTo(address newImplementation) external ifAdmin {
                                _upgradeToAndCall(newImplementation, bytes(""), false);
                            }
                            /**
                             * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                             * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                             * proxied contract.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                             */
                            function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                                _upgradeToAndCall(newImplementation, data, true);
                            }
                            /**
                             * @dev Returns the current admin.
                             */
                            function _admin() internal view virtual returns (address) {
                                return _getAdmin();
                            }
                            /**
                             * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                             */
                            function _beforeFallback() internal virtual override {
                                require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                                super._beforeFallback();
                            }
                            function _getAdmin() internal view virtual override returns (address) {
                                return _ADMIN;
                            }
                        }
                        

                        File 11 of 12: OptimizedTransparentUpgradeableProxy
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        /**
                         * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
                         * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
                         * be specified by overriding the virtual {_implementation} function.
                         * 
                         * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
                         * different contract through the {_delegate} function.
                         * 
                         * The success and return data of the delegated call will be returned back to the caller of the proxy.
                         */
                        abstract contract Proxy {
                            /**
                             * @dev Delegates the current call to `implementation`.
                             * 
                             * This function does not return to its internall call site, it will return directly to the external caller.
                             */
                            function _delegate(address implementation) internal {
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    // Copy msg.data. We take full control of memory in this inline assembly
                                    // block because it will not return to Solidity code. We overwrite the
                                    // Solidity scratch pad at memory position 0.
                                    calldatacopy(0, 0, calldatasize())
                                    // Call the implementation.
                                    // out and outsize are 0 because we don't know the size yet.
                                    let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                                    // Copy the returned data.
                                    returndatacopy(0, 0, returndatasize())
                                    switch result
                                    // delegatecall returns 0 on error.
                                    case 0 { revert(0, returndatasize()) }
                                    default { return(0, returndatasize()) }
                                }
                            }
                            /**
                             * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
                             * and {_fallback} should delegate.
                             */
                            function _implementation() internal virtual view returns (address);
                            /**
                             * @dev Delegates the current call to the address returned by `_implementation()`.
                             * 
                             * This function does not return to its internall call site, it will return directly to the external caller.
                             */
                            function _fallback() internal {
                                _beforeFallback();
                                _delegate(_implementation());
                            }
                            /**
                             * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
                             * function in the contract matches the call data.
                             */
                            fallback () payable external {
                                _fallback();
                            }
                            /**
                             * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
                             * is empty.
                             */
                            receive () payable external {
                                _fallback();
                            }
                            /**
                             * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
                             * call, or as part of the Solidity `fallback` or `receive` functions.
                             * 
                             * If overriden should call `super._beforeFallback()`.
                             */
                            function _beforeFallback() internal virtual {
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        import "./Proxy.sol";
                        import "../utils/Address.sol";
                        /**
                         * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
                         * implementation address that can be changed. This address is stored in storage in the location specified by
                         * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
                         * implementation behind the proxy.
                         * 
                         * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see
                         * {TransparentUpgradeableProxy}.
                         */
                        contract UpgradeableProxy is Proxy {
                            /**
                             * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
                             * 
                             * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
                             * function call, and allows initializating the storage of the proxy like a Solidity constructor.
                             */
                            constructor(address _logic, bytes memory _data) payable {
                                assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                                _setImplementation(_logic);
                                if(_data.length > 0) {
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success,) = _logic.delegatecall(_data);
                                    require(success);
                                }
                            }
                            /**
                             * @dev Emitted when the implementation is upgraded.
                             */
                            event Upgraded(address indexed implementation);
                            /**
                             * @dev Storage slot with the address of the current implementation.
                             * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
                             * validated in the constructor.
                             */
                            bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                            /**
                             * @dev Returns the current implementation address.
                             */
                            function _implementation() internal override view returns (address impl) {
                                bytes32 slot = _IMPLEMENTATION_SLOT;
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    impl := sload(slot)
                                }
                            }
                            /**
                             * @dev Upgrades the proxy to a new implementation.
                             * 
                             * Emits an {Upgraded} event.
                             */
                            function _upgradeTo(address newImplementation) internal {
                                _setImplementation(newImplementation);
                                emit Upgraded(newImplementation);
                            }
                            /**
                             * @dev Stores a new address in the EIP1967 implementation slot.
                             */
                            function _setImplementation(address newImplementation) private {
                                require(Address.isContract(newImplementation), "UpgradeableProxy: new implementation is not a contract");
                                bytes32 slot = _IMPLEMENTATION_SLOT;
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    sstore(slot, newImplementation)
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        /**
                         * @dev Collection of functions related to the address type
                         */
                        library Address {
                            /**
                             * @dev Returns true if `account` is a contract.
                             *
                             * [IMPORTANT]
                             * ====
                             * It is unsafe to assume that an address for which this function returns
                             * false is an externally-owned account (EOA) and not a contract.
                             *
                             * Among others, `isContract` will return false for the following
                             * types of addresses:
                             *
                             *  - an externally-owned account
                             *  - a contract in construction
                             *  - an address where a contract will be created
                             *  - an address where a contract lived, but was destroyed
                             * ====
                             */
                            function isContract(address account) internal view returns (bool) {
                                // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
                                // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
                                // for accounts without code, i.e. `keccak256('')`
                                bytes32 codehash;
                                bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
                                // solhint-disable-next-line no-inline-assembly
                                assembly { codehash := extcodehash(account) }
                                return (codehash != accountHash && codehash != 0x0);
                            }
                            /**
                             * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                             * `recipient`, forwarding all available gas and reverting on errors.
                             *
                             * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                             * of certain opcodes, possibly making contracts go over the 2300 gas limit
                             * imposed by `transfer`, making them unable to receive funds via
                             * `transfer`. {sendValue} removes this limitation.
                             *
                             * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                             *
                             * IMPORTANT: because control is transferred to `recipient`, care must be
                             * taken to not create reentrancy vulnerabilities. Consider using
                             * {ReentrancyGuard} or the
                             * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                             */
                            function sendValue(address payable recipient, uint256 amount) internal {
                                require(address(this).balance >= amount, "Address: insufficient balance");
                                // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                                (bool success, ) = recipient.call{ value: amount }("");
                                require(success, "Address: unable to send value, recipient may have reverted");
                            }
                            /**
                             * @dev Performs a Solidity function call using a low level `call`. A
                             * plain`call` is an unsafe replacement for a function call: use this
                             * function instead.
                             *
                             * If `target` reverts with a revert reason, it is bubbled up by this
                             * function (like regular Solidity function calls).
                             *
                             * Returns the raw returned data. To convert to the expected return value,
                             * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                             *
                             * Requirements:
                             *
                             * - `target` must be a contract.
                             * - calling `target` with `data` must not revert.
                             *
                             * _Available since v3.1._
                             */
                            function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                              return functionCall(target, data, "Address: low-level call failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                             * `errorMessage` as a fallback revert reason when `target` reverts.
                             *
                             * _Available since v3.1._
                             */
                            function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                                return _functionCallWithValue(target, data, 0, errorMessage);
                            }
                            /**
                             * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                             * but also transferring `value` wei to `target`.
                             *
                             * Requirements:
                             *
                             * - the calling contract must have an ETH balance of at least `value`.
                             * - the called Solidity function must be `payable`.
                             *
                             * _Available since v3.1._
                             */
                            function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                                return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                            }
                            /**
                             * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                             * with `errorMessage` as a fallback revert reason when `target` reverts.
                             *
                             * _Available since v3.1._
                             */
                            function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                                require(address(this).balance >= value, "Address: insufficient balance for call");
                                return _functionCallWithValue(target, data, value, errorMessage);
                            }
                            function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
                                require(isContract(target), "Address: call to non-contract");
                                // solhint-disable-next-line avoid-low-level-calls
                                (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
                                if (success) {
                                    return returndata;
                                } else {
                                    // Look for revert reason and bubble it up if present
                                    if (returndata.length > 0) {
                                        // The easiest way to bubble the revert reason is using memory via assembly
                                        // solhint-disable-next-line no-inline-assembly
                                        assembly {
                                            let returndata_size := mload(returndata)
                                            revert(add(32, returndata), returndata_size)
                                        }
                                    } else {
                                        revert(errorMessage);
                                    }
                                }
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        import "../openzeppelin/proxy/UpgradeableProxy.sol";
                        /**
                         * @dev This contract implements a proxy that is upgradeable by an admin.
                         *
                         * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
                         * clashing], which can potentially be used in an attack, this contract uses the
                         * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
                         * things that go hand in hand:
                         *
                         * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
                         * that call matches one of the admin functions exposed by the proxy itself.
                         * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
                         * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
                         * "admin cannot fallback to proxy target".
                         *
                         * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
                         * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
                         * to sudden errors when trying to call a function from the proxy implementation.
                         *
                         * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
                         * you should think of the `ProxyAdmin` instance as the real administrative inerface of your proxy.
                         */
                        contract OptimizedTransparentUpgradeableProxy is UpgradeableProxy {
                            address internal immutable _ADMIN;
                            /**
                             * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
                             * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.
                             */
                            constructor(
                                address initialLogic,
                                address initialAdmin,
                                bytes memory _data
                            ) payable UpgradeableProxy(initialLogic, _data) {
                                assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                                bytes32 slot = _ADMIN_SLOT;
                                _ADMIN = initialAdmin;
                                // still store it to work with EIP-1967
                                // solhint-disable-next-line no-inline-assembly
                                assembly {
                                    sstore(slot, initialAdmin)
                                }
                            }
                            /**
                             * @dev Storage slot with the admin of the contract.
                             * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
                             * validated in the constructor.
                             */
                            bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                            /**
                             * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
                             */
                            modifier ifAdmin() {
                                if (msg.sender == _admin()) {
                                    _;
                                } else {
                                    _fallback();
                                }
                            }
                            /**
                             * @dev Returns the current admin.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
                             *
                             * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                             * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                             * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
                             */
                            function admin() external ifAdmin returns (address) {
                                return _admin();
                            }
                            /**
                             * @dev Returns the current implementation.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
                             *
                             * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
                             * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
                             * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
                             */
                            function implementation() external ifAdmin returns (address) {
                                return _implementation();
                            }
                            /**
                             * @dev Upgrade the implementation of the proxy.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
                             */
                            function upgradeTo(address newImplementation) external ifAdmin {
                                _upgradeTo(newImplementation);
                            }
                            /**
                             * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
                             * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
                             * proxied contract.
                             *
                             * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
                             */
                            function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                                _upgradeTo(newImplementation);
                                // solhint-disable-next-line avoid-low-level-calls
                                (bool success, ) = newImplementation.delegatecall(data);
                                require(success);
                            }
                            /**
                             * @dev Returns the current admin.
                             */
                            function _admin() internal view returns (address adm) {
                                return _ADMIN;
                            }
                            /**
                             * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
                             */
                            function _beforeFallback() internal virtual override {
                                require(msg.sender != _admin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                                super._beforeFallback();
                            }
                        }
                        

                        File 12 of 12: TreasuryV2
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity 0.7.6;
                        import "./interfaces/ILayerZeroTreasury.sol";
                        import "@openzeppelin/contracts/access/Ownable.sol";
                        import "@openzeppelin/contracts/math/SafeMath.sol";
                        import "./interfaces/ILayerZeroUltraLightNodeV2.sol";
                        contract TreasuryV2 is ILayerZeroTreasury, Ownable {
                            using SafeMath for uint;
                            uint public nativeBP;
                            uint public zroFee;
                            bool public feeEnabled;
                            bool public zroEnabled;
                            ILayerZeroUltraLightNodeV2 public uln;
                            event NativeBP(uint bp);
                            event ZroFee(uint zroFee);
                            event FeeEnabled(bool feeEnabled);
                            event ZroEnabled(bool zroEnabled);
                            constructor(address _ulnv2) {
                                uln = ILayerZeroUltraLightNodeV2(_ulnv2);
                            }
                            function getFees(bool payInZro, uint relayerFee, uint oracleFee) external view override returns (uint) {
                                if (feeEnabled) {
                                    if (payInZro) {
                                        require(zroEnabled, "LayerZero: ZRO is not enabled");
                                        return zroFee;
                                    } else {
                                        return relayerFee.add(oracleFee).mul(nativeBP).div(10000);
                                    }
                                }
                                return 0;
                            }
                            function setFeeEnabled(bool _feeEnabled) external onlyOwner {
                                feeEnabled = _feeEnabled;
                                emit FeeEnabled(_feeEnabled);
                            }
                            function setZroEnabled(bool _zroEnabled) external onlyOwner {
                                zroEnabled = _zroEnabled;
                                emit ZroEnabled(_zroEnabled);
                            }
                            function setNativeBP(uint _nativeBP) external onlyOwner {
                                nativeBP = _nativeBP;
                                emit NativeBP(_nativeBP);
                            }
                            function setZroFee(uint _zroFee) external onlyOwner {
                                zroFee = _zroFee;
                                emit ZroFee(_zroFee);
                            }
                            function withdrawZROFromULN(address _to, uint _amount) external onlyOwner {
                                uln.withdrawZRO(_to, _amount);
                            }
                            function withdrawNativeFromULN(address payable _to, uint _amount) external onlyOwner {
                                uln.withdrawNative(_to, _amount);
                            }
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.5.0;
                        interface ILayerZeroTreasury {
                            function getFees(bool payInZro, uint relayerFee, uint oracleFee) external view returns (uint);
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        import "../utils/Context.sol";
                        /**
                         * @dev Contract module which provides a basic access control mechanism, where
                         * there is an account (an owner) that can be granted exclusive access to
                         * specific functions.
                         *
                         * By default, the owner account will be the one that deploys the contract. This
                         * can later be changed with {transferOwnership}.
                         *
                         * This module is used through inheritance. It will make available the modifier
                         * `onlyOwner`, which can be applied to your functions to restrict their use to
                         * the owner.
                         */
                        abstract contract Ownable is Context {
                            address private _owner;
                            event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                            /**
                             * @dev Initializes the contract setting the deployer as the initial owner.
                             */
                            constructor () {
                                address msgSender = _msgSender();
                                _owner = msgSender;
                                emit OwnershipTransferred(address(0), msgSender);
                            }
                            /**
                             * @dev Returns the address of the current owner.
                             */
                            function owner() public view virtual returns (address) {
                                return _owner;
                            }
                            /**
                             * @dev Throws if called by any account other than the owner.
                             */
                            modifier onlyOwner() {
                                require(owner() == _msgSender(), "Ownable: caller is not the owner");
                                _;
                            }
                            /**
                             * @dev Leaves the contract without owner. It will not be possible to call
                             * `onlyOwner` functions anymore. Can only be called by the current owner.
                             *
                             * NOTE: Renouncing ownership will leave the contract without an owner,
                             * thereby removing any functionality that is only available to the owner.
                             */
                            function renounceOwnership() public virtual onlyOwner {
                                emit OwnershipTransferred(_owner, address(0));
                                _owner = address(0);
                            }
                            /**
                             * @dev Transfers ownership of the contract to a new account (`newOwner`).
                             * Can only be called by the current owner.
                             */
                            function transferOwnership(address newOwner) public virtual onlyOwner {
                                require(newOwner != address(0), "Ownable: new owner is the zero address");
                                emit OwnershipTransferred(_owner, newOwner);
                                _owner = newOwner;
                            }
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity ^0.7.0;
                        /**
                         * @dev Wrappers over Solidity's arithmetic operations with added overflow
                         * checks.
                         *
                         * Arithmetic operations in Solidity wrap on overflow. This can easily result
                         * in bugs, because programmers usually assume that an overflow raises an
                         * error, which is the standard behavior in high level programming languages.
                         * `SafeMath` restores this intuition by reverting the transaction when an
                         * operation overflows.
                         *
                         * Using this library instead of the unchecked operations eliminates an entire
                         * class of bugs, so it's recommended to use it always.
                         */
                        library SafeMath {
                            /**
                             * @dev Returns the addition of two unsigned integers, with an overflow flag.
                             *
                             * _Available since v3.4._
                             */
                            function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                uint256 c = a + b;
                                if (c < a) return (false, 0);
                                return (true, c);
                            }
                            /**
                             * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                             *
                             * _Available since v3.4._
                             */
                            function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                if (b > a) return (false, 0);
                                return (true, a - b);
                            }
                            /**
                             * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                             *
                             * _Available since v3.4._
                             */
                            function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                                // benefit is lost if 'b' is also tested.
                                // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                                if (a == 0) return (true, 0);
                                uint256 c = a * b;
                                if (c / a != b) return (false, 0);
                                return (true, c);
                            }
                            /**
                             * @dev Returns the division of two unsigned integers, with a division by zero flag.
                             *
                             * _Available since v3.4._
                             */
                            function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                if (b == 0) return (false, 0);
                                return (true, a / b);
                            }
                            /**
                             * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                             *
                             * _Available since v3.4._
                             */
                            function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                                if (b == 0) return (false, 0);
                                return (true, a % b);
                            }
                            /**
                             * @dev Returns the addition of two unsigned integers, reverting on
                             * overflow.
                             *
                             * Counterpart to Solidity's `+` operator.
                             *
                             * Requirements:
                             *
                             * - Addition cannot overflow.
                             */
                            function add(uint256 a, uint256 b) internal pure returns (uint256) {
                                uint256 c = a + b;
                                require(c >= a, "SafeMath: addition overflow");
                                return c;
                            }
                            /**
                             * @dev Returns the subtraction of two unsigned integers, reverting on
                             * overflow (when the result is negative).
                             *
                             * Counterpart to Solidity's `-` operator.
                             *
                             * Requirements:
                             *
                             * - Subtraction cannot overflow.
                             */
                            function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                                require(b <= a, "SafeMath: subtraction overflow");
                                return a - b;
                            }
                            /**
                             * @dev Returns the multiplication of two unsigned integers, reverting on
                             * overflow.
                             *
                             * Counterpart to Solidity's `*` operator.
                             *
                             * Requirements:
                             *
                             * - Multiplication cannot overflow.
                             */
                            function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                                if (a == 0) return 0;
                                uint256 c = a * b;
                                require(c / a == b, "SafeMath: multiplication overflow");
                                return c;
                            }
                            /**
                             * @dev Returns the integer division of two unsigned integers, reverting on
                             * division by zero. The result is rounded towards zero.
                             *
                             * Counterpart to Solidity's `/` operator. Note: this function uses a
                             * `revert` opcode (which leaves remaining gas untouched) while Solidity
                             * uses an invalid opcode to revert (consuming all remaining gas).
                             *
                             * Requirements:
                             *
                             * - The divisor cannot be zero.
                             */
                            function div(uint256 a, uint256 b) internal pure returns (uint256) {
                                require(b > 0, "SafeMath: division by zero");
                                return a / b;
                            }
                            /**
                             * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                             * reverting when dividing by zero.
                             *
                             * Counterpart to Solidity's `%` operator. This function uses a `revert`
                             * opcode (which leaves remaining gas untouched) while Solidity uses an
                             * invalid opcode to revert (consuming all remaining gas).
                             *
                             * Requirements:
                             *
                             * - The divisor cannot be zero.
                             */
                            function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                                require(b > 0, "SafeMath: modulo by zero");
                                return a % b;
                            }
                            /**
                             * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                             * overflow (when the result is negative).
                             *
                             * CAUTION: This function is deprecated because it requires allocating memory for the error
                             * message unnecessarily. For custom revert reasons use {trySub}.
                             *
                             * Counterpart to Solidity's `-` operator.
                             *
                             * Requirements:
                             *
                             * - Subtraction cannot overflow.
                             */
                            function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                require(b <= a, errorMessage);
                                return a - b;
                            }
                            /**
                             * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                             * division by zero. The result is rounded towards zero.
                             *
                             * CAUTION: This function is deprecated because it requires allocating memory for the error
                             * message unnecessarily. For custom revert reasons use {tryDiv}.
                             *
                             * Counterpart to Solidity's `/` operator. Note: this function uses a
                             * `revert` opcode (which leaves remaining gas untouched) while Solidity
                             * uses an invalid opcode to revert (consuming all remaining gas).
                             *
                             * Requirements:
                             *
                             * - The divisor cannot be zero.
                             */
                            function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                require(b > 0, errorMessage);
                                return a / b;
                            }
                            /**
                             * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                             * reverting with custom message when dividing by zero.
                             *
                             * CAUTION: This function is deprecated because it requires allocating memory for the error
                             * message unnecessarily. For custom revert reasons use {tryMod}.
                             *
                             * Counterpart to Solidity's `%` operator. This function uses a `revert`
                             * opcode (which leaves remaining gas untouched) while Solidity uses an
                             * invalid opcode to revert (consuming all remaining gas).
                             *
                             * Requirements:
                             *
                             * - The divisor cannot be zero.
                             */
                            function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                                require(b > 0, errorMessage);
                                return a % b;
                            }
                        }
                        // SPDX-License-Identifier: BUSL-1.1
                        pragma solidity >=0.7.0;
                        pragma abicoder v2;
                        interface ILayerZeroUltraLightNodeV2 {
                            // Relayer functions
                            function validateTransactionProof(uint16 _srcChainId, address _dstAddress, uint _gasLimit, bytes32 _lookupHash, bytes32 _blockData, bytes calldata _transactionProof) external;
                            // an Oracle delivers the block data using updateHash()
                            function updateHash(uint16 _srcChainId, bytes32 _lookupHash, uint _confirmations, bytes32 _blockData) external;
                            // can only withdraw the receivable of the msg.sender
                            function withdrawNative(address payable _to, uint _amount) external;
                            function withdrawZRO(address _to, uint _amount) external;
                            // view functions
                            function getAppConfig(uint16 _remoteChainId, address _userApplicationAddress) external view returns (ApplicationConfiguration memory);
                            function accruedNativeFee(address _address) external view returns (uint);
                            struct ApplicationConfiguration {
                                uint16 inboundProofLibraryVersion;
                                uint64 inboundBlockConfirmations;
                                address relayer;
                                uint16 outboundProofType;
                                uint64 outboundBlockConfirmations;
                                address oracle;
                            }
                            event HashReceived(uint16 indexed srcChainId, address indexed oracle, bytes32 lookupHash, bytes32 blockData, uint confirmations);
                            event RelayerParams(bytes adapterParams, uint16 outboundProofType);
                            event Packet(bytes payload);
                            event InvalidDst(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);
                            event PacketReceived(uint16 indexed srcChainId, bytes srcAddress, address indexed dstAddress, uint64 nonce, bytes32 payloadHash);
                            event AppConfigUpdated(address indexed userApplication, uint indexed configType, bytes newConfig);
                            event AddInboundProofLibraryForChain(uint16 indexed chainId, address lib);
                            event EnableSupportedOutboundProof(uint16 indexed chainId, uint16 proofType);
                            event SetChainAddressSize(uint16 indexed chainId, uint size);
                            event SetDefaultConfigForChainId(uint16 indexed chainId, uint16 inboundProofLib, uint64 inboundBlockConfirm, address relayer, uint16 outboundProofType, uint64 outboundBlockConfirm, address oracle);
                            event SetDefaultAdapterParamsForChainId(uint16 indexed chainId, uint16 indexed proofType, bytes adapterParams);
                            event SetLayerZeroToken(address indexed tokenAddress);
                            event SetRemoteUln(uint16 indexed chainId, bytes32 uln);
                            event SetTreasury(address indexed treasuryAddress);
                            event WithdrawZRO(address indexed msgSender, address indexed to, uint amount);
                            event WithdrawNative(address indexed msgSender, address indexed to, uint amount);
                        }
                        // SPDX-License-Identifier: MIT
                        pragma solidity >=0.6.0 <0.8.0;
                        /*
                         * @dev Provides information about the current execution context, including the
                         * sender of the transaction and its data. While these are generally available
                         * via msg.sender and msg.data, they should not be accessed in such a direct
                         * manner, since when dealing with GSN meta-transactions the account sending and
                         * paying for execution may not be the actual sender (as far as an application
                         * is concerned).
                         *
                         * This contract is only required for intermediate, library-like contracts.
                         */
                        abstract contract Context {
                            function _msgSender() internal view virtual returns (address payable) {
                                return msg.sender;
                            }
                            function _msgData() internal view virtual returns (bytes memory) {
                                this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                                return msg.data;
                            }
                        }