{"SafeMath.sol":{"content":"pragma solidity ^0.6.12;\r\n\r\n// ----------------------------------------------------------------------------\r\n// Safe maths\r\n// ----------------------------------------------------------------------------\r\nlibrary SafeMath {\r\n    function add(uint a, uint b) internal pure returns (uint c) {\r\n        c = a + b;\r\n        require(c \u003e= a, \u0027SafeMath:INVALID_ADD\u0027);\r\n    }\r\n\r\n    function sub(uint a, uint b) internal pure returns (uint c) {\r\n        require(b \u003c= a, \u0027SafeMath:OVERFLOW_SUB\u0027);\r\n        c = a - b;\r\n    }\r\n\r\n    function mul(uint a, uint b, uint decimal) internal pure returns (uint) {\r\n        uint dc = 10**decimal;\r\n        uint c0 = a * b;\r\n        require(a == 0 || c0 / a == b, \"SafeMath: multiple overflow\");\r\n        uint c1 = c0 + (dc / 2);\r\n        require(c1 \u003e= c0, \"SafeMath: multiple overflow\");\r\n        uint c2 = c1 / dc;\r\n        return c2;\r\n    }\r\n\r\n    function div(uint256 a, uint256 b, uint decimal) internal pure returns (uint256) {\r\n        require(b != 0, \"SafeMath: division by zero\");\r\n        uint dc = 10**decimal;\r\n        uint c0 = a * dc;\r\n        require(a == 0 || c0 / a == dc, \"SafeMath: division internal\");\r\n        uint c1 = c0 + (b / 2);\r\n        require(c1 \u003e= c0, \"SafeMath: division internal\");\r\n        uint c2 = c1 / b;\r\n        return c2;\r\n    }\r\n}\r\n"},"TransferHelper.sol":{"content":"pragma solidity ^0.6.12;\r\n\r\n// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false\r\nlibrary TransferHelper {\r\n    function safeApprove(\r\n        address token,\r\n        address to,\r\n        uint256 value\r\n    ) internal {\r\n        // bytes4(keccak256(bytes(\u0027approve(address,uint256)\u0027)));\r\n        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));\r\n        require(\r\n            success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool))),\r\n            \u0027TransferHelper::safeApprove: approve failed\u0027\r\n        );\r\n    }\r\n\r\n    function safeTransfer(\r\n        address token,\r\n        address to,\r\n        uint256 value\r\n    ) internal {\r\n        // bytes4(keccak256(bytes(\u0027transfer(address,uint256)\u0027)));\r\n        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));\r\n        require(\r\n            success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool))),\r\n            \u0027TransferHelper::safeTransfer: transfer failed\u0027\r\n        );\r\n    }\r\n\r\n    function safeTransferFrom(\r\n        address token,\r\n        address from,\r\n        address to,\r\n        uint256 value\r\n    ) internal {\r\n        // bytes4(keccak256(bytes(\u0027transferFrom(address,address,uint256)\u0027)));\r\n        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));\r\n        require(\r\n            success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool))),\r\n            \u0027TransferHelper::transferFrom: transferFrom failed\u0027\r\n        );\r\n    }\r\n\r\n    function safeTransferETH(address to, uint256 value) internal {\r\n        (bool success, ) = to.call{value: value}(new bytes(0));\r\n        require(success, \u0027TransferHelper::safeTransferETH: ETH transfer failed\u0027);\r\n    }\r\n}\r\n"},"TubeChiefV2.sol":{"content":"pragma solidity ^0.6.12;\r\n\r\nimport \u0027./TransferHelper.sol\u0027;\r\nimport \u0027./SafeMath.sol\u0027;\r\n\r\ncontract TubeChiefV2 {\r\n    using SafeMath for uint;\r\n\r\n    struct PoolInfo {\r\n        address lpTokenAddress;  // the LP token pair address\r\n        uint rewardPerBlock;     // number of TUBE will mint per block\r\n        uint lastDevBlockNo;     // record token mint to development last block number\r\n        uint lastLotBlockNo;     // record token mint to lottery last block number\r\n        uint lastStakeBlockNo;   // record token mint to staking last block number\r\n        uint lastJackpotBlockNo; // record token mint to jackpot last block number\r\n        uint accLpStaked;        // accumulate number of LP token user staked\r\n        uint accLastBlockNo;     // record last pass in block number\r\n        uint multiplier;         // reward multiplier\r\n        uint accTokenPerShare;   // accumulated token per share\r\n        bool locked;             // pool is locked\r\n        bool finished;           // pool is finished. Disable stake into pool\r\n    }\r\n\r\n    struct UserPoolInfo {\r\n        uint lpStaked;       // user staked LP\r\n        uint rewardDebt;     // user debt\r\n        uint lastClaimBlock; // last block number user retrieve reward\r\n    }\r\n\r\n    mapping(uint =\u003e PoolInfo) public pools; // dynamic pool container (pool ID =\u003e pool related data)\r\n    mapping(address =\u003e uint[]) poolIdByLp;  // pool ids recorder (LP token =\u003e pool ids)\r\n\r\n    // user pool allocate (user addr =\u003e (\u003cpool ID\u003e =\u003e user pool data))\r\n    mapping(address =\u003e mapping(uint =\u003e UserPoolInfo)) public users;\r\n    \r\n    // allow to manage defarm operation\r\n    mapping(address =\u003e bool) public defarm_permission;\r\n\r\n    // allow to manage functional operation\r\n    mapping(address =\u003e bool) public access_permission;\r\n\r\n    address public owner;         // owner of tube chief\r\n    address public tube;          // the TUBE token\r\n    address public devaddr;       // development address\r\n    address public lotaddr;       // lottery address\r\n    address public dfstakeaddr;   // sub staking address\r\n    address public dfjackpotaddr; // sub jackpot address\r\n    address public treasury;      // minting purpose. treasury or TUBE token\r\n    \r\n    uint public poolLength; // next pool id. current length is (poolLength - 1)\r\n\r\n    uint public FARMER    = 500000000000000000;\r\n    uint public DEV       = 100000000000000000;\r\n    uint public LOTTERY   = 150000000000000000;\r\n    uint public DFSTAKE   = 25000000000000000;\r\n    uint public DFJACKPOT = 225000000000000000;\r\n    \r\n    uint constant DECIMAL = 18;\r\n\r\n    event CreatePool(address lpTokenAddress, uint rewardPerBlock, uint poolId);\r\n    event UpdatePool(uint poolId, uint rewardPerBlock, uint multiplier, bool locked);\r\n    event UpdateDevAddr(address devaddr);\r\n    event UpdateLotAddr(address lotaddr);\r\n    event UpdateDefarmAddress(address dfstakeaddr, address dfjackpotaddr);\r\n    event UpdateAllocation(uint farmer, uint dev, uint lot, uint staking, uint jackpot);\r\n    event UpdateDefarmPermission(address _address, bool status);\r\n    event UpdateAccessPermission(address _address, bool status);\r\n    event UpdateTreasury(address _address);\r\n    event UpdatePoolFinish(uint poolId, bool finished);\r\n    event Stake(uint poolId, uint amount);\r\n    event Claim(uint poolId, uint amount, uint claimable);\r\n    event TransferCompany(address old_owner, address new_owner);\r\n    event TransferDev(uint poolId, address receiver, uint amount);\r\n    event TransferLottery(uint poolId, address receiver, uint amount);\r\n    event TransferStaking(uint poolId, address receiver, uint amount);\r\n    event TransferJackpotReward(address receiver, uint amount);\r\n\r\n    modifier onlyOwner {\r\n        require(msg.sender == owner, \u0027NOT OWNER\u0027);\r\n        _;\r\n    }\r\n    \r\n    modifier hasDefarmPermission() {\r\n        require(defarm_permission[msg.sender], \u0027NO DEFARM PERMISSION\u0027);\r\n        _;\r\n    }\r\n\r\n    modifier hasAccessPermission() {\r\n        require(access_permission[msg.sender], \u0027NO ACCESS PERMISSION\u0027);\r\n        _;\r\n    }\r\n\r\n    constructor (address _tube, address _devaddr, address _lotaddr) public {\r\n        owner   = msg.sender;\r\n        tube    = _tube;\r\n        devaddr = _devaddr;\r\n        lotaddr = _lotaddr;\r\n        defarm_permission[msg.sender] = true;\r\n        access_permission[msg.sender] = true;\r\n    }\r\n\r\n    // create new pool. only owner executable\r\n    // XX do not create twice on same LP token. reward will mess up if you do\r\n    function createPool(address _lpTokenAddress, uint _rewardPerBlock, uint _multiplier) public hasAccessPermission {\r\n        require(_lpTokenAddress != address(0), \u0027CREATE_POOL_EMPTY_ADDRESS\u0027);\r\n\r\n        emit CreatePool(_lpTokenAddress, _rewardPerBlock, poolLength);\r\n        pools[poolLength].lpTokenAddress     = _lpTokenAddress;\r\n        pools[poolLength].rewardPerBlock     = _rewardPerBlock;\r\n        pools[poolLength].multiplier         = _multiplier;\r\n        pools[poolLength].accLastBlockNo     = block.number;\r\n        pools[poolLength].lastDevBlockNo     = block.number;\r\n        pools[poolLength].lastLotBlockNo     = block.number;\r\n        pools[poolLength].lastStakeBlockNo   = block.number;\r\n        pools[poolLength].lastJackpotBlockNo = block.number;\r\n        poolIdByLp[_lpTokenAddress].push(poolLength);\r\n        poolLength = poolLength.add(1);\r\n    }\r\n\r\n    // update pool setting, edit wisely. only owner executable\r\n    function updatePool(uint poolId, uint _rewardPerBlock, uint _multiplier, bool _locked) public hasAccessPermission {\r\n        _updateAccTokenPerShare(poolId);\r\n        pools[poolId].rewardPerBlock = _rewardPerBlock;\r\n        pools[poolId].multiplier     = _multiplier;\r\n        pools[poolId].locked         = _locked;\r\n        emit UpdatePool(poolId, _rewardPerBlock, _multiplier, _locked);\r\n    }\r\n    \r\n    // update pool is finish. user not allow to stake into pool. only owner executable\r\n    function updatePoolFinish(uint poolId, bool _finished) public hasAccessPermission {\r\n        pools[poolId].finished = _finished;\r\n        emit UpdatePoolFinish(poolId, _finished);\r\n    }\r\n\r\n    // update development address. only owner executable\r\n    function updateDevAddr(address _address) public hasAccessPermission {\r\n        devaddr = _address;\r\n        emit UpdateDevAddr(devaddr);\r\n    }\r\n\r\n    // update lottery address. only owner executable\r\n    function updateLotAddr(address _address) public hasAccessPermission {\r\n        lotaddr = _address;\r\n        emit UpdateLotAddr(lotaddr);\r\n    }\r\n    \r\n    // update defarm addresses. only owner executable\r\n    function updateDefarmAddress(address _dfstakeaddr, address _dfjackpotaddr) public hasAccessPermission {\r\n        dfstakeaddr   = _dfstakeaddr;\r\n        dfjackpotaddr = _dfjackpotaddr;\r\n        emit UpdateDefarmAddress(dfstakeaddr, dfjackpotaddr);\r\n    }\r\n\r\n    // update treasury allow chief mint TUBE token. only owner executable\r\n    function updateTreasury(address _address) public hasAccessPermission {\r\n        treasury = _address;\r\n        emit UpdateTreasury(_address);\r\n    }\r\n\r\n    // update allocation for each sector. only owner executable\r\n    function updateAllocation(uint _farmer, uint _dev, uint _lot, uint _dfstake, uint _dfjackpot) public hasAccessPermission {\r\n        require(_farmer.add(_dev).add(_lot).add(_dfstake).add(_dfjackpot) == 1000000000000000000, \"invalid allocation\");\r\n        FARMER    = _farmer;\r\n        DEV       = _dev;\r\n        LOTTERY   = _lot;\r\n        DFSTAKE   = _dfstake;\r\n        DFJACKPOT = _dfjackpot;\r\n        emit UpdateAllocation(_farmer, _dev, _lot, _dfstake, _dfjackpot);\r\n    }\r\n\r\n    // update defarm permission. only owner executable\r\n    function updateDefarmPermission(address _address, bool status) public onlyOwner {\r\n        defarm_permission[_address] = status;\r\n        emit UpdateDefarmPermission(_address, status);\r\n    }\r\n\r\n    // update access permission. only owner executable\r\n    function updateAccessPermission(address _address, bool status) public onlyOwner {\r\n        access_permission[_address] = status;\r\n        emit UpdateAccessPermission(_address, status);\r\n    }\r\n\r\n    // stake LP token to earn TUBE\r\n    function stake(uint poolId, uint amount) public {\r\n        require(pools[poolId].lpTokenAddress != address(0), \u0027STAKE_POOL_NOT_EXIST\u0027);\r\n        require(pools[poolId].locked == false, \u0027STAKE_POOL_LOCKED\u0027);\r\n        require(pools[poolId].finished == false, \u0027STAKE_POOL_FINISHED\u0027);\r\n\r\n        claim(poolId, 0);\r\n        TransferHelper.safeTransferFrom(pools[poolId].lpTokenAddress, msg.sender, address(this), amount);\r\n        pools[poolId].accLpStaked = pools[poolId].accLpStaked.add(amount);\r\n        users[msg.sender][poolId].lpStaked       = users[msg.sender][poolId].lpStaked.add(amount);\r\n        users[msg.sender][poolId].lastClaimBlock = block.number;\r\n        users[msg.sender][poolId].rewardDebt     = pools[poolId].accTokenPerShare.mul(users[msg.sender][poolId].lpStaked, DECIMAL);\r\n\r\n        emit Stake(poolId, amount);\r\n    }\r\n\r\n    // claim TUBE token. input LP token to exit pool\r\n    function claim(uint poolId, uint amount) public {\r\n        require(pools[poolId].lpTokenAddress != address(0), \u0027CLAIM_POOL_NOT_EXIST\u0027);\r\n        require(pools[poolId].locked == false, \u0027CLAIM_POOL_LOCKED\u0027);\r\n        \r\n        _updateAccTokenPerShare(poolId);\r\n\r\n        uint claimable = _getRewardAmount(poolId);\r\n        if (claimable \u003e 0) {\r\n            IMint(treasury).farmMint(address(this), claimable);\r\n            TransferHelper.safeTransfer(tube, msg.sender, claimable);\r\n            users[msg.sender][poolId].lastClaimBlock = block.number;\r\n        }\r\n\r\n        if (amount \u003e 0) {\r\n            TransferHelper.safeTransfer(pools[poolId].lpTokenAddress, msg.sender, amount);\r\n            users[msg.sender][poolId].lpStaked = users[msg.sender][poolId].lpStaked.sub(amount);\r\n            pools[poolId].accLpStaked = pools[poolId].accLpStaked.sub(amount);\r\n        }\r\n\r\n        // emit if necessary. cost saving\r\n        if (claimable \u003e 0 || amount \u003e 0) {\r\n            emit Claim(poolId, amount, claimable);\r\n        }\r\n\r\n        // update the user reward debt at this moment\r\n        users[msg.sender][poolId].rewardDebt = pools[poolId].accTokenPerShare.mul(users[msg.sender][poolId].lpStaked, DECIMAL);\r\n    }\r\n\r\n    // get token per share with current block number\r\n    function getAccTokenInfo(uint poolId) public view returns (uint) {\r\n        if (pools[poolId].accLpStaked \u003c= 0) {\r\n            return 0;\r\n        }\r\n\r\n        uint reward_block = pools[poolId].rewardPerBlock;\r\n        uint multiplier   = pools[poolId].multiplier;\r\n        uint total_staked = pools[poolId].accLpStaked;\r\n        uint pending      = block.number.sub(pools[poolId].accLastBlockNo);\r\n        pending           = pending * 10**DECIMAL; // cast to \"wei\" unit\r\n        uint result       = reward_block.mul(multiplier, DECIMAL).mul(pending, DECIMAL).mul(FARMER, DECIMAL);\r\n\r\n        return result.div(total_staked, DECIMAL);\r\n    }\r\n\r\n    // emergency collect token from the contract. only owner executable\r\n    function emergencyCollectToken(address token, uint amount) public onlyOwner {\r\n        TransferHelper.safeTransfer(token, owner, amount);\r\n    }\r\n\r\n    // emergency collect eth from the contract. only owner executable\r\n    function emergencyCollectEth(uint amount) public onlyOwner {\r\n        address payable owner_address = payable(owner);\r\n        TransferHelper.safeTransferETH(owner_address, amount);\r\n    }\r\n\r\n    // transfer ownership. proceed wisely. only owner executable\r\n    function transferCompany(address new_owner) public onlyOwner {\r\n        emit TransferCompany(owner, new_owner);\r\n        owner = new_owner;\r\n    }\r\n\r\n    // transfer mintable token to development address\r\n    function transferDev(uint poolId) public hasAccessPermission {\r\n        uint mintable = getExMintable(poolId, keccak256(\"DEV\"));\r\n        require(mintable \u003e 0, \u0027TRANSFER_DEV_EMPTY\u0027);\r\n        require(devaddr != address(0), \u0027EMPTY DEV ADDRESS\u0027);\r\n        IMint(treasury).farmMint(address(this), mintable);\r\n        TransferHelper.safeTransfer(tube, devaddr, mintable);\r\n        pools[poolId].lastDevBlockNo = block.number;\r\n        emit TransferDev(poolId, devaddr, mintable);\r\n    }\r\n\r\n    // transfer mintable token to lottery address\r\n    function transferLottery(uint poolId) public hasAccessPermission {\r\n        uint mintable = getExMintable(poolId, keccak256(\"LOTTERY\"));\r\n        require(mintable \u003e 0, \u0027TRANSFER_LOT_EMPTY\u0027);\r\n        require(lotaddr != address(0), \u0027EMPTY LOTTERY ADDRESS\u0027);\r\n        IMint(treasury).farmMint(address(this), mintable);\r\n        TransferHelper.safeTransfer(tube, lotaddr, mintable);\r\n        pools[poolId].lastLotBlockNo = block.number;\r\n        emit TransferLottery(poolId, lotaddr, mintable);\r\n    }\r\n    \r\n    // transfer mintable token to sub staking\r\n    function transferStaking(uint poolId) public hasDefarmPermission {\r\n        uint mintable = getExMintable(poolId, keccak256(\"STAKING\"));\r\n        require(dfstakeaddr != address(0), \u0027EMPTY DFSTAKE ADDRESS\u0027);\r\n        \r\n        if (mintable \u003e 0) {\r\n            IMint(treasury).farmMint(address(this), mintable);\r\n            TransferHelper.safeTransfer(tube, dfstakeaddr, mintable);\r\n            pools[poolId].lastStakeBlockNo = block.number;\r\n            emit TransferStaking(poolId, dfstakeaddr, mintable);\r\n        }\r\n    }\r\n    \r\n    // transfer mintable token to sub jackpot\r\n    function transferJackpotReward() public hasDefarmPermission returns (uint) {\r\n        require(dfjackpotaddr != address(0), \u0027EMPTY DFJACKPOT ADDRESS\u0027);\r\n        \r\n        uint mintable = getJackpotReward();\r\n\r\n        if (mintable \u003e 0) {\r\n            IMint(treasury).farmMint(address(this), mintable);\r\n            TransferHelper.safeTransfer(tube, dfjackpotaddr, mintable);\r\n            emit TransferJackpotReward(dfjackpotaddr, mintable);\r\n        }\r\n        \r\n        for (uint i = 0; i \u003c= poolLength.sub(1); i++) {\r\n            pools[i].lastJackpotBlockNo = block.number;\r\n        }\r\n        \r\n        return mintable;\r\n    }\r\n\r\n    // retrieve the mintable amount\r\n    function getExMintable(uint poolId, bytes32 category) public view returns (uint) {\r\n        uint last_block   = 0;\r\n        uint rate         = 0;\r\n\r\n        if (category == keccak256(\"DEV\")) {\r\n            last_block = pools[poolId].lastDevBlockNo;\r\n            rate       = DEV;\r\n        } else if (category == keccak256(\"LOTTERY\")) {\r\n            last_block = pools[poolId].lastLotBlockNo;\r\n            rate       = LOTTERY;\r\n        } else if (category == keccak256(\"STAKING\")) {\r\n            last_block = pools[poolId].lastStakeBlockNo;\r\n            rate       = DFSTAKE;\r\n        } else if (category == keccak256(\"JACKPOT\")) {\r\n            last_block = pools[poolId].lastJackpotBlockNo;\r\n            rate       = DFJACKPOT;\r\n        } else {\r\n            last_block = 0;\r\n            rate       = 0;\r\n        }\r\n        \r\n        uint block_diff = block.number.sub(last_block);\r\n        block_diff      = block_diff * 10**DECIMAL;\r\n\r\n        return block_diff.mul(pools[poolId].rewardPerBlock, DECIMAL).mul(pools[poolId].multiplier, DECIMAL).mul(rate, DECIMAL);\r\n    }\r\n    \r\n    // retrieve jackpot reward allocation\r\n    function getJackpotReward() public view returns (uint) {\r\n        uint reward = 0;\r\n        for (uint i = 0; i \u003c= poolLength.sub(1); i++) {\r\n            reward = reward.add(getExMintable(i, keccak256(\"JACKPOT\")));\r\n        }\r\n        return reward;\r\n    }\r\n\r\n    // retrieve pool ids by LP token address\r\n    function getPidByLpToken(address _lpTokenAddress) public view returns (uint[] memory) {\r\n        return poolIdByLp[_lpTokenAddress];\r\n    }\r\n\r\n    // retrieve user reward info on the pool with current block number\r\n    function getUserReward(uint poolId) public view returns (uint, uint, uint, uint, uint) {\r\n        uint accTokenPerShare = getAccTokenInfo(poolId);\r\n        accTokenPerShare      = accTokenPerShare.add(pools[poolId].accTokenPerShare);\r\n        \r\n        uint claimable = accTokenPerShare.mul(users[msg.sender][poolId].lpStaked, DECIMAL).sub(users[msg.sender][poolId].rewardDebt);\r\n        return (block.number, claimable, accTokenPerShare, users[msg.sender][poolId].lpStaked, users[msg.sender][poolId].rewardDebt);\r\n    }\r\n    \r\n    function _updateAccTokenPerShare(uint poolId) internal {\r\n        uint result = getAccTokenInfo(poolId);\r\n        pools[poolId].accTokenPerShare = pools[poolId].accTokenPerShare.add(result);\r\n        pools[poolId].accLastBlockNo   = block.number;\r\n    }\r\n\r\n    function _getRewardAmount(uint poolId) view internal returns (uint) {\r\n        if (pools[poolId].accLpStaked \u003c= 0) {\r\n            return (0);\r\n        }\r\n\r\n        uint user_staked = users[msg.sender][poolId].lpStaked;\r\n        uint user_debt   = users[msg.sender][poolId].rewardDebt;\r\n        uint claimable   = pools[poolId].accTokenPerShare.mul(user_staked, DECIMAL).sub(user_debt);\r\n\r\n        return (claimable);\r\n    }\r\n\r\n    fallback() external payable {\r\n    }\r\n}\r\n\r\ninterface IMint {\r\n    function farmMint(address _address, uint amount) external;\r\n}\r\n"}}

{"SafeMath.sol":{"content":"pragma solidity ^0.6.12;\r\n\r\n// ----------------------------------------------------------------------------\r\n// Safe maths\r\n// ----------------------------------------------------------------------------\r\nlibrary SafeMath {\r\n    function add(uint a, uint b) internal pure returns (uint c) {\r\n        c = a + b;\r\n        require(c \u003e= a, \u0027SafeMath:INVALID_ADD\u0027);\r\n    }\r\n\r\n    function sub(uint a, uint b) internal pure returns (uint c) {\r\n        require(b \u003c= a, \u0027SafeMath:OVERFLOW_SUB\u0027);\r\n        c = a - b;\r\n    }\r\n\r\n    function mul(uint a, uint b, uint decimal) internal pure returns (uint) {\r\n        uint dc = 10**decimal;\r\n        uint c0 = a * b;\r\n        require(a == 0 || c0 / a == b, \"SafeMath: multiple overflow\");\r\n        uint c1 = c0 + (dc / 2);\r\n        require(c1 \u003e= c0, \"SafeMath: multiple overflow\");\r\n        uint c2 = c1 / dc;\r\n        return c2;\r\n    }\r\n\r\n    function div(uint256 a, uint256 b, uint decimal) internal pure returns (uint256) {\r\n        require(b != 0, \"SafeMath: division by zero\");\r\n        uint dc = 10**decimal;\r\n        uint c0 = a * dc;\r\n        require(a == 0 || c0 / a == dc, \"SafeMath: division internal\");\r\n        uint c1 = c0 + (b / 2);\r\n        require(c1 \u003e= c0, \"SafeMath: division internal\");\r\n        uint c2 = c1 / b;\r\n        return c2;\r\n    }\r\n}\r\n"},"TubeToken.sol":{"content":"pragma solidity ^0.6.12;\r\n\r\nimport \u0027./SafeMath.sol\u0027;\r\n\r\n// ----------------------------------------------------------------------------\r\n// ERC Token Standard #20 Interface\r\n// https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20-token-standard.md\r\n// ----------------------------------------------------------------------------\r\nabstract contract ERC20Interface {\r\n  function totalSupply() public virtual view returns (uint);\r\n  function balanceOf(address tokenOwner) public virtual view returns (uint balance);\r\n  function allowance(address tokenOwner, address spender) public virtual view returns (uint remaining);\r\n  function transfer(address to, uint tokens) public virtual returns (bool success);\r\n  function approve(address spender, uint tokens) public virtual returns (bool success);\r\n  function transferFrom(address from, address to, uint tokens) public virtual returns (bool success);\r\n\r\n  event Transfer(address indexed from, address indexed to, uint tokens);\r\n  event Approval(address indexed tokenOwner, address indexed spender, uint tokens);\r\n}\r\n\r\n// ----------------------------------------------------------------------------\r\n// Contract function to receive approval and execute function in one call\r\n//\r\n// Borrowed from MiniMeToken\r\n// ----------------------------------------------------------------------------\r\nabstract contract ApproveAndCallFallBack {\r\n  function receiveApproval(address from, uint256 tokens, address token, bytes memory data) public virtual;\r\n}\r\n\r\n// ----------------------------------------------------------------------------\r\n// Owned contract\r\n// ----------------------------------------------------------------------------\r\ncontract Owned {\r\n  address public owner;\r\n  address public newOwner;\r\n\r\n  event OwnershipTransferred(address indexed _from, address indexed _to);\r\n\r\n  constructor() public {\r\n      owner = msg.sender;\r\n  }\r\n\r\n  modifier onlyOwner {\r\n    require(msg.sender == owner);\r\n    _;\r\n  }\r\n\r\n  function transferOwnership(address _newOwner) public onlyOwner {\r\n    newOwner = _newOwner;\r\n  }\r\n  function acceptOwnership() public {\r\n    require(msg.sender == newOwner);\r\n    emit OwnershipTransferred(owner, newOwner);\r\n    owner = newOwner;\r\n    newOwner = address(0);\r\n  }\r\n}\r\n\r\n// ----------------------------------------------------------------------------\r\n// ERC20 Token, with the addition of symbol, name and decimals and an\r\n// initial fixed supply\r\n// ----------------------------------------------------------------------------\r\ncontract TubeToken is ERC20Interface, Owned {\r\n  using SafeMath for uint;\r\n\r\n  address public chief; // the Tube Chief address\r\n\r\n  string public symbol;\r\n  string public  name;\r\n  uint8 public decimals;\r\n  uint public _totalSupply;\r\n\r\n  mapping(address =\u003e uint) balances;\r\n  mapping(address =\u003e mapping(address =\u003e uint)) allowed;\r\n\r\n  // only cheif contract able to interact the important function !\r\n  modifier onlyChief {\r\n      require(chief != address(0), \u0027CHIEF MISSING\u0027);\r\n      require(msg.sender == chief, \u0027ACCESS_FORBIDDEN\u0027);\r\n      _;\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Constructor\r\n  // ------------------------------------------------------------------------\r\n  constructor() public {\r\n    symbol   = \"TUBE2\";\r\n    name     = \"TUBE2\";\r\n    decimals = 18;\r\n    _totalSupply    = 0 * 10**uint(decimals);\r\n    balances[owner] = _totalSupply;\r\n    emit Transfer(address(0), owner, _totalSupply);\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Total supply\r\n  // ------------------------------------------------------------------------\r\n  function totalSupply() public override view returns (uint) {\r\n    return _totalSupply  - balances[address(0)];\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Get the token balance for account `tokenOwner`\r\n  // ------------------------------------------------------------------------\r\n  function balanceOf(address tokenOwner) public override view returns (uint balance) {\r\n    return balances[tokenOwner];\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Transfer the balance from token owner\u0027s account to `to` account\r\n  // - Owner\u0027s account must have sufficient balance to transfer\r\n  // - 0 value transfers are allowed\r\n  // ------------------------------------------------------------------------\r\n  function transfer(address to, uint tokens) public override returns (bool success) {\r\n    balances[msg.sender] = balances[msg.sender].sub(tokens);\r\n    balances[to] = balances[to].add(tokens);\r\n    emit Transfer(msg.sender, to, tokens);\r\n    return true;\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Token owner can approve for `spender` to transferFrom(...) `tokens`\r\n  // from the token owner\u0027s account\r\n  //\r\n  // https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20-token-standard.md\r\n  // recommends that there are no checks for the approval double-spend attack\r\n  // as this should be implemented in user interfaces\r\n  // ------------------------------------------------------------------------\r\n  function approve(address spender, uint tokens) public override returns (bool success) {\r\n    allowed[msg.sender][spender] = tokens;\r\n    emit Approval(msg.sender, spender, tokens);\r\n    return true;\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Transfer `tokens` from the `from` account to the `to` account\r\n  //\r\n  // The calling account must already have sufficient tokens approve(...)-d\r\n  // for spending from the `from` account and\r\n  // - From account must have sufficient balance to transfer\r\n  // - Spender must have sufficient allowance to transfer\r\n  // - 0 value transfers are allowed\r\n  // ------------------------------------------------------------------------\r\n  function transferFrom(address from, address to, uint tokens) public override returns (bool success) {\r\n    balances[from] = balances[from].sub(tokens);\r\n    allowed[from][msg.sender] = allowed[from][msg.sender].sub(tokens);\r\n    balances[to] = balances[to].add(tokens);\r\n    emit Transfer(from, to, tokens);\r\n    return true;\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Returns the amount of tokens approved by the owner that can be\r\n  // transferred to the spender\u0027s account\r\n  // ------------------------------------------------------------------------\r\n  function allowance(address tokenOwner, address spender) public view override returns (uint remaining) {\r\n    return allowed[tokenOwner][spender];\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Token owner can approve for `spender` to transferFrom(...) `tokens`\r\n  // from the token owner\u0027s account. The `spender` contract function\r\n  // `receiveApproval(...)` is then executed\r\n  // ------------------------------------------------------------------------\r\n  function approveAndCall(address spender, uint tokens, bytes memory data) public returns (bool success) {\r\n    allowed[msg.sender][spender] = tokens;\r\n    emit Approval(msg.sender, spender, tokens);\r\n    ApproveAndCallFallBack(spender).receiveApproval(msg.sender, tokens, address(this), data);\r\n    return true;\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Update chief address from chief contract\r\n  // ------------------------------------------------------------------------\r\n  function updateChief(address _chief) public onlyOwner {\r\n      chief = _chief;\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Mint token\r\n  // ------------------------------------------------------------------------\r\n  function mint(address _address, uint amount) public onlyOwner {\r\n      _mint(_address, amount);\r\n  }\r\n\r\n  function farmMint(address _address, uint amount) external onlyChief {\r\n      _mint(_address, amount);\r\n  }\r\n\r\n  function _mint(address account, uint256 amount) internal {\r\n    require(account != address(0), \"ERC20: mint to the zero address\");\r\n    _totalSupply = _totalSupply.add(amount);\r\n    balances[account] = balances[account].add(amount);\r\n    emit Transfer(address(0), account, amount);\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Burn token\r\n  // ------------------------------------------------------------------------\r\n  function burn(address account, uint256 amount) public onlyOwner {\r\n        require(account != address(0), \"ERC20: burn from the zero address\");\r\n        require(balances[account] \u003e= amount, \"ERC20: burn amount exceeds balance\");\r\n        balances[account] = balances[account].sub(amount);\r\n        _totalSupply = _totalSupply.sub(amount);\r\n        emit Transfer(account, address(0), amount);\r\n    }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Don\u0027t accept ETH\r\n  // ------------------------------------------------------------------------\r\n  fallback() external payable {\r\n    revert();\r\n  }\r\n\r\n  // ------------------------------------------------------------------------\r\n  // Owner can transfer out any accidentally sent ERC20 tokens\r\n  // ------------------------------------------------------------------------\r\n  function transferAnyERC20Token(address tokenAddress, uint tokens) public onlyOwner returns (bool success) {\r\n    return ERC20Interface(tokenAddress).transfer(owner, tokens);\r\n  }\r\n}\r\n"}}

{"IERC20.sol":{"content":"pragma solidity \u003e=0.5.0;\n\ninterface IERC20 {\n    event Approval(address indexed owner, address indexed spender, uint value);\n    event Transfer(address indexed from, address indexed to, uint value);\n\n    function name() external view returns (string memory);\n    function symbol() external view returns (string memory);\n    function decimals() external view returns (uint8);\n    function totalSupply() external view returns (uint);\n    function balanceOf(address owner) external view returns (uint);\n    function allowance(address owner, address spender) external view returns (uint);\n\n    function approve(address spender, uint value) external returns (bool);\n    function transfer(address to, uint value) external returns (bool);\n    function transferFrom(address from, address to, uint value) external returns (bool);\n}\n"},"IUniswapV2Callee.sol":{"content":"pragma solidity \u003e=0.5.0;\n\ninterface IUniswapV2Callee {\n    function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;\n}\n"},"IUniswapV2ERC20.sol":{"content":"pragma solidity \u003e=0.5.0;\n\ninterface IUniswapV2ERC20 {\n    event Approval(address indexed owner, address indexed spender, uint value);\n    event Transfer(address indexed from, address indexed to, uint value);\n\n    function name() external pure returns (string memory);\n    function symbol() external pure returns (string memory);\n    function decimals() external pure returns (uint8);\n    function totalSupply() external view returns (uint);\n    function balanceOf(address owner) external view returns (uint);\n    function allowance(address owner, address spender) external view returns (uint);\n\n    function approve(address spender, uint value) external returns (bool);\n    function transfer(address to, uint value) external returns (bool);\n    function transferFrom(address from, address to, uint value) external returns (bool);\n\n    function DOMAIN_SEPARATOR() external view returns (bytes32);\n    function PERMIT_TYPEHASH() external pure returns (bytes32);\n    function nonces(address owner) external view returns (uint);\n\n    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;\n}\n"},"IUniswapV2Factory.sol":{"content":"pragma solidity \u003e=0.5.0;\r\n\r\ninterface IUniswapV2Factory {\r\n    event PairCreated(address indexed token0, address indexed token1, address pair, uint);\r\n\r\n    function feeTo() external view returns (address);\r\n    function feeToSetter() external view returns (address);\r\n\r\n    function getPair(address tokenA, address tokenB) external view returns (address pair);\r\n    function allPairs(uint) external view returns (address pair);\r\n    function allPairsLength() external view returns (uint);\r\n\r\n    function createPair(address tokenA, address tokenB) external returns (address pair);\r\n\r\n    function setFeeTo(address) external;\r\n    function setFeeToSetter(address) external;\r\n}\r\n"},"IUniswapV2Pair.sol":{"content":"pragma solidity \u003e=0.5.0;\n\ninterface IUniswapV2Pair {\n    event Approval(address indexed owner, address indexed spender, uint value);\n    event Transfer(address indexed from, address indexed to, uint value);\n\n    function name() external pure returns (string memory);\n    function symbol() external pure returns (string memory);\n    function decimals() external pure returns (uint8);\n    function totalSupply() external view returns (uint);\n    function balanceOf(address owner) external view returns (uint);\n    function allowance(address owner, address spender) external view returns (uint);\n\n    function approve(address spender, uint value) external returns (bool);\n    function transfer(address to, uint value) external returns (bool);\n    function transferFrom(address from, address to, uint value) external returns (bool);\n\n    function DOMAIN_SEPARATOR() external view returns (bytes32);\n    function PERMIT_TYPEHASH() external pure returns (bytes32);\n    function nonces(address owner) external view returns (uint);\n\n    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;\n\n    event Mint(address indexed sender, uint amount0, uint amount1);\n    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);\n    event Swap(\n        address indexed sender,\n        uint amount0In,\n        uint amount1In,\n        uint amount0Out,\n        uint amount1Out,\n        address indexed to\n    );\n    event Sync(uint112 reserve0, uint112 reserve1);\n\n    function MINIMUM_LIQUIDITY() external pure returns (uint);\n    function factory() external view returns (address);\n    function token0() external view returns (address);\n    function token1() external view returns (address);\n    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);\n    function price0CumulativeLast() external view returns (uint);\n    function price1CumulativeLast() external view returns (uint);\n    function kLast() external view returns (uint);\n\n    function mint(address to) external returns (uint liquidity);\n    function burn(address to) external returns (uint amount0, uint amount1);\n    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;\n    function skim(address to) external;\n    function sync() external;\n\n    function initialize(address, address) external;\n}\n"},"Math.sol":{"content":"pragma solidity =0.5.16;\n\n// a library for performing various math operations\n\nlibrary Math {\n    function min(uint x, uint y) internal pure returns (uint z) {\n        z = x \u003c y ? x : y;\n    }\n\n    // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)\n    function sqrt(uint y) internal pure returns (uint z) {\n        if (y \u003e 3) {\n            z = y;\n            uint x = y / 2 + 1;\n            while (x \u003c z) {\n                z = x;\n                x = (y / x + x) / 2;\n            }\n        } else if (y != 0) {\n            z = 1;\n        }\n    }\n}\n"},"SafeMath.sol":{"content":"pragma solidity =0.5.16;\n\n// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)\n\nlibrary SafeMath {\n    function add(uint x, uint y) internal pure returns (uint z) {\n        require((z = x + y) \u003e= x, \u0027ds-math-add-overflow\u0027);\n    }\n\n    function sub(uint x, uint y) internal pure returns (uint z) {\n        require((z = x - y) \u003c= x, \u0027ds-math-sub-underflow\u0027);\n    }\n\n    function mul(uint x, uint y) internal pure returns (uint z) {\n        require(y == 0 || (z = x * y) / y == x, \u0027ds-math-mul-overflow\u0027);\n    }\n}\n"},"UniswapV2ERC20.sol":{"content":"pragma solidity =0.5.16;\r\n\r\nimport \u0027./IUniswapV2ERC20.sol\u0027;\r\nimport \u0027./SafeMath.sol\u0027;\r\n\r\ncontract UniswapV2ERC20 is IUniswapV2ERC20 {\r\n    using SafeMath for uint;\r\n\r\n    string public constant name = \u0027TUBE2-LP\u0027;\r\n    string public constant symbol = \u0027TUBE2-LP\u0027;\r\n    uint8 public constant decimals = 18;\r\n    uint  public totalSupply;\r\n    mapping(address =\u003e uint) public balanceOf;\r\n    mapping(address =\u003e mapping(address =\u003e uint)) public allowance;\r\n\r\n    bytes32 public DOMAIN_SEPARATOR;\r\n    // keccak256(\"Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)\");\r\n    bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;\r\n    mapping(address =\u003e uint) public nonces;\r\n\r\n    event Approval(address indexed owner, address indexed spender, uint value);\r\n    event Transfer(address indexed from, address indexed to, uint value);\r\n\r\n    constructor() public {\r\n        uint chainId;\r\n        assembly {\r\n            chainId := chainid\r\n        }\r\n        DOMAIN_SEPARATOR = keccak256(\r\n            abi.encode(\r\n                keccak256(\u0027EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)\u0027),\r\n                keccak256(bytes(name)),\r\n                keccak256(bytes(\u00271\u0027)),\r\n                chainId,\r\n                address(this)\r\n            )\r\n        );\r\n    }\r\n\r\n    function _mint(address to, uint value) internal {\r\n        totalSupply = totalSupply.add(value);\r\n        balanceOf[to] = balanceOf[to].add(value);\r\n        emit Transfer(address(0), to, value);\r\n    }\r\n\r\n    function _burn(address from, uint value) internal {\r\n        balanceOf[from] = balanceOf[from].sub(value);\r\n        totalSupply = totalSupply.sub(value);\r\n        emit Transfer(from, address(0), value);\r\n    }\r\n\r\n    function _approve(address owner, address spender, uint value) private {\r\n        allowance[owner][spender] = value;\r\n        emit Approval(owner, spender, value);\r\n    }\r\n\r\n    function _transfer(address from, address to, uint value) private {\r\n        balanceOf[from] = balanceOf[from].sub(value);\r\n        balanceOf[to] = balanceOf[to].add(value);\r\n        emit Transfer(from, to, value);\r\n    }\r\n\r\n    function approve(address spender, uint value) external returns (bool) {\r\n        _approve(msg.sender, spender, value);\r\n        return true;\r\n    }\r\n\r\n    function transfer(address to, uint value) external returns (bool) {\r\n        _transfer(msg.sender, to, value);\r\n        return true;\r\n    }\r\n\r\n    function transferFrom(address from, address to, uint value) external returns (bool) {\r\n        if (allowance[from][msg.sender] != uint(-1)) {\r\n            allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);\r\n        }\r\n        _transfer(from, to, value);\r\n        return true;\r\n    }\r\n\r\n    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {\r\n        require(deadline \u003e= block.timestamp, \u0027UniswapV2: EXPIRED\u0027);\r\n        bytes32 digest = keccak256(\r\n            abi.encodePacked(\r\n                \u0027\\x19\\x01\u0027,\r\n                DOMAIN_SEPARATOR,\r\n                keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))\r\n            )\r\n        );\r\n        address recoveredAddress = ecrecover(digest, v, r, s);\r\n        require(recoveredAddress != address(0) \u0026\u0026 recoveredAddress == owner, \u0027UniswapV2: INVALID_SIGNATURE\u0027);\r\n        _approve(owner, spender, value);\r\n    }\r\n}\r\n"},"UniswapV2Pair.sol":{"content":"pragma solidity =0.5.16;\r\n\r\nimport \u0027./IUniswapV2Pair.sol\u0027;\r\nimport \u0027./UniswapV2ERC20.sol\u0027;\r\nimport \u0027./Math.sol\u0027;\r\nimport \u0027./UQ112x112.sol\u0027;\r\nimport \u0027./IERC20.sol\u0027;\r\nimport \u0027./IUniswapV2Factory.sol\u0027;\r\nimport \u0027./IUniswapV2Callee.sol\u0027;\r\n\r\ncontract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {\r\n    using SafeMath  for uint;\r\n    using UQ112x112 for uint224;\r\n\r\n    uint public constant MINIMUM_LIQUIDITY = 10**3;\r\n    bytes4 private constant SELECTOR = bytes4(keccak256(bytes(\u0027transfer(address,uint256)\u0027)));\r\n\r\n    address public factory;\r\n    address public token0;\r\n    address public token1;\r\n\r\n    uint112 private reserve0;           // uses single storage slot, accessible via getReserves\r\n    uint112 private reserve1;           // uses single storage slot, accessible via getReserves\r\n    uint32  private blockTimestampLast; // uses single storage slot, accessible via getReserves\r\n\r\n    uint public price0CumulativeLast;\r\n    uint public price1CumulativeLast;\r\n    uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event\r\n\r\n    uint private unlocked = 1;\r\n    modifier lock() {\r\n        require(unlocked == 1, \u0027UniswapV2: LOCKED\u0027);\r\n        unlocked = 0;\r\n        _;\r\n        unlocked = 1;\r\n    }\r\n\r\n    function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {\r\n        _reserve0 = reserve0;\r\n        _reserve1 = reserve1;\r\n        _blockTimestampLast = blockTimestampLast;\r\n    }\r\n\r\n    function _safeTransfer(address token, address to, uint value) private {\r\n        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));\r\n        require(success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool))), \u0027UniswapV2: TRANSFER_FAILED\u0027);\r\n    }\r\n\r\n    event Mint(address indexed sender, uint amount0, uint amount1);\r\n    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);\r\n    event Swap(\r\n        address indexed sender,\r\n        uint amount0In,\r\n        uint amount1In,\r\n        uint amount0Out,\r\n        uint amount1Out,\r\n        address indexed to\r\n    );\r\n    event Sync(uint112 reserve0, uint112 reserve1);\r\n\r\n    constructor() public {\r\n        factory = msg.sender;\r\n    }\r\n\r\n    // called once by the factory at time of deployment\r\n    function initialize(address _token0, address _token1) external {\r\n        require(msg.sender == factory, \u0027UniswapV2: FORBIDDEN\u0027); // sufficient check\r\n        token0 = _token0;\r\n        token1 = _token1;\r\n    }\r\n\r\n    // update reserves and, on the first call per block, price accumulators\r\n    function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {\r\n        require(balance0 \u003c= uint112(-1) \u0026\u0026 balance1 \u003c= uint112(-1), \u0027UniswapV2: OVERFLOW\u0027);\r\n        uint32 blockTimestamp = uint32(block.timestamp % 2**32);\r\n        uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired\r\n        if (timeElapsed \u003e 0 \u0026\u0026 _reserve0 != 0 \u0026\u0026 _reserve1 != 0) {\r\n            // * never overflows, and + overflow is desired\r\n            price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;\r\n            price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;\r\n        }\r\n        reserve0 = uint112(balance0);\r\n        reserve1 = uint112(balance1);\r\n        blockTimestampLast = blockTimestamp;\r\n        emit Sync(reserve0, reserve1);\r\n    }\r\n\r\n    // if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)\r\n    function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {\r\n        address feeTo = IUniswapV2Factory(factory).feeTo();\r\n        feeOn = feeTo != address(0);\r\n        uint _kLast = kLast; // gas savings\r\n        if (feeOn) {\r\n            if (_kLast != 0) {\r\n                uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));\r\n                uint rootKLast = Math.sqrt(_kLast);\r\n                if (rootK \u003e rootKLast) {\r\n                    uint numerator = totalSupply.mul(rootK.sub(rootKLast));\r\n                    uint denominator = rootK.mul(5).add(rootKLast);\r\n                    uint liquidity = numerator / denominator;\r\n                    if (liquidity \u003e 0) _mint(feeTo, liquidity);\r\n                }\r\n            }\r\n        } else if (_kLast != 0) {\r\n            kLast = 0;\r\n        }\r\n    }\r\n\r\n    // this low-level function should be called from a contract which performs important safety checks\r\n    function mint(address to) external lock returns (uint liquidity) {\r\n        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings\r\n        uint balance0 = IERC20(token0).balanceOf(address(this));\r\n        uint balance1 = IERC20(token1).balanceOf(address(this));\r\n        uint amount0 = balance0.sub(_reserve0);\r\n        uint amount1 = balance1.sub(_reserve1);\r\n\r\n        bool feeOn = _mintFee(_reserve0, _reserve1);\r\n        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee\r\n        if (_totalSupply == 0) {\r\n            liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);\r\n           _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens\r\n        } else {\r\n            liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);\r\n        }\r\n        require(liquidity \u003e 0, \u0027UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED\u0027);\r\n        _mint(to, liquidity);\r\n\r\n        _update(balance0, balance1, _reserve0, _reserve1);\r\n        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date\r\n        emit Mint(msg.sender, amount0, amount1);\r\n    }\r\n\r\n    // this low-level function should be called from a contract which performs important safety checks\r\n    function burn(address to) external lock returns (uint amount0, uint amount1) {\r\n        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings\r\n        address _token0 = token0;                                // gas savings\r\n        address _token1 = token1;                                // gas savings\r\n        uint balance0 = IERC20(_token0).balanceOf(address(this));\r\n        uint balance1 = IERC20(_token1).balanceOf(address(this));\r\n        uint liquidity = balanceOf[address(this)];\r\n\r\n        bool feeOn = _mintFee(_reserve0, _reserve1);\r\n        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee\r\n        amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution\r\n        amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution\r\n        require(amount0 \u003e 0 \u0026\u0026 amount1 \u003e 0, \u0027UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED\u0027);\r\n        _burn(address(this), liquidity);\r\n        _safeTransfer(_token0, to, amount0);\r\n        _safeTransfer(_token1, to, amount1);\r\n        balance0 = IERC20(_token0).balanceOf(address(this));\r\n        balance1 = IERC20(_token1).balanceOf(address(this));\r\n\r\n        _update(balance0, balance1, _reserve0, _reserve1);\r\n        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date\r\n        emit Burn(msg.sender, amount0, amount1, to);\r\n    }\r\n\r\n    // this low-level function should be called from a contract which performs important safety checks\r\n    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {\r\n        require(amount0Out \u003e 0 || amount1Out \u003e 0, \u0027UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT\u0027);\r\n        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings\r\n        require(amount0Out \u003c _reserve0 \u0026\u0026 amount1Out \u003c _reserve1, \u0027UniswapV2: INSUFFICIENT_LIQUIDITY\u0027);\r\n\r\n        uint balance0;\r\n        uint balance1;\r\n        { // scope for _token{0,1}, avoids stack too deep errors\r\n        address _token0 = token0;\r\n        address _token1 = token1;\r\n        require(to != _token0 \u0026\u0026 to != _token1, \u0027UniswapV2: INVALID_TO\u0027);\r\n        if (amount0Out \u003e 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens\r\n        if (amount1Out \u003e 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens\r\n        if (data.length \u003e 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);\r\n        balance0 = IERC20(_token0).balanceOf(address(this));\r\n        balance1 = IERC20(_token1).balanceOf(address(this));\r\n        }\r\n        uint amount0In = balance0 \u003e _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;\r\n        uint amount1In = balance1 \u003e _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;\r\n        require(amount0In \u003e 0 || amount1In \u003e 0, \u0027UniswapV2: INSUFFICIENT_INPUT_AMOUNT\u0027);\r\n        { // scope for reserve{0,1}Adjusted, avoids stack too deep errors\r\n        uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));\r\n        uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));\r\n        require(balance0Adjusted.mul(balance1Adjusted) \u003e= uint(_reserve0).mul(_reserve1).mul(1000**2), \u0027UniswapV2: K\u0027);\r\n        }\r\n\r\n        _update(balance0, balance1, _reserve0, _reserve1);\r\n        emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);\r\n    }\r\n\r\n    // force balances to match reserves\r\n    function skim(address to) external lock {\r\n        address _token0 = token0; // gas savings\r\n        address _token1 = token1; // gas savings\r\n        _safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));\r\n        _safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));\r\n    }\r\n\r\n    // force reserves to match balances\r\n    function sync() external lock {\r\n        _update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);\r\n    }\r\n}\r\n"},"UQ112x112.sol":{"content":"pragma solidity =0.5.16;\n\n// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))\n\n// range: [0, 2**112 - 1]\n// resolution: 1 / 2**112\n\nlibrary UQ112x112 {\n    uint224 constant Q112 = 2**112;\n\n    // encode a uint112 as a UQ112x112\n    function encode(uint112 y) internal pure returns (uint224 z) {\n        z = uint224(y) * Q112; // never overflows\n    }\n\n    // divide a UQ112x112 by a uint112, returning a UQ112x112\n    function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {\n        z = x / uint224(y);\n    }\n}\n"}}