pragma solidity ^0.5.8;


interface ILiquidityPool {
    
    
    function take(address _token, uint256 _amount) external;

    
    
    function deposit(address _token, uint256 _amount) external returns (uint256);

    
    
    function withdraw(address _token, uint256 _amount) external;

    
    
    
    function isEther(address _ether) external pure returns (bool);
}

interface IRebalancer {
    
    
    
    
    
    
    function giveUnbalancedPosition(address _negToken, uint256 _negAmount, address _posToken, uint256 _posAmount) external payable;
}

contract Context {
    
    
    constructor () internal { }
    

    function _msgSender() internal view returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view returns (bytes memory) {
        this; 
        return msg.data;
    }
}

contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    
    constructor () internal {
        _owner = _msgSender();
        emit OwnershipTransferred(address(0), _owner);
    }

    
    function owner() public view returns (address) {
        return _owner;
    }

    
    modifier onlyOwner() {
        require(isOwner(), "Ownable: caller is not the owner");
        _;
    }

    
    function isOwner() public view returns (bool) {
        return _msgSender() == _owner;
    }

    
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

interface IERC20 {
    
    function totalSupply() external view returns (uint256);

    
    function balanceOf(address account) external view returns (uint256);

    
    function transfer(address recipient, uint256 amount) external returns (bool);

    
    function allowance(address owner, address spender) external view returns (uint256);

    
    function approve(address spender, uint256 amount) external returns (bool);

    
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    
    event Transfer(address indexed from, address indexed to, uint256 value);

    
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

library SafeMath {
    
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    
    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;
    }

    
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        
        require(b > 0, errorMessage);
        uint256 c = a / b;
        

        return c;
    }

    
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    
    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }

    
    function balanceOf(address account) public view returns (uint256) {
        return _balances[account];
    }

    
    function transfer(address recipient, uint256 amount) public returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    
    function allowance(address owner, address spender) public view returns (uint256) {
        return _allowances[owner][spender];
    }

    
    function approve(address spender, uint256 amount) public returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    
    function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    
    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    
    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

    
    function _transfer(address sender, address recipient, uint256 amount) internal {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    
    function _mint(address account, uint256 amount) internal {
        require(account != address(0), "ERC20: mint to the zero address");

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

     
    function _burn(address account, uint256 amount) internal {
        require(account != address(0), "ERC20: burn from the zero address");

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    
    function _approve(address owner, address spender, uint256 amount) internal {
        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);
    }

    
    function _burnFrom(address account, uint256 amount) internal {
        _burn(account, amount);
        _approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "ERC20: burn amount exceeds allowance"));
    }
}

library Address {
    
    function isContract(address account) internal view returns (bool) {
        
        
        

        
        
        
        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        
        assembly { codehash := extcodehash(account) }
        return (codehash != 0x0 && codehash != accountHash);
    }

    
    function toPayable(address account) internal pure returns (address payable) {
        return address(uint160(account));
    }

    
    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");
    }
}

library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        
        
        
        
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    
    function callOptionalReturn(IERC20 token, bytes memory data) private {
        
        

        
        
        
        
        
        require(address(token).isContract(), "SafeERC20: call to non-contract");

        
        (bool success, bytes memory returndata) = address(token).call(data);
        require(success, "SafeERC20: low-level call failed");

        if (returndata.length > 0) { 
            
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

contract CanReclaimTokens is Ownable {
    using SafeERC20 for ERC20;

    mapping(address => bool) private recoverableTokensBlacklist;

    function blacklistRecoverableToken(address _token) public onlyOwner {
        recoverableTokensBlacklist[_token] = true;
    }

    
    
    function recoverTokens(address _token) external onlyOwner {
        require(!recoverableTokensBlacklist[_token], "CanReclaimTokens: token is not recoverable");

        if (_token == address(0x0)) {
            msg.sender.transfer(address(this).balance);
        } else {
            ERC20(_token).safeTransfer(msg.sender, ERC20(_token).balanceOf(address(this)));
        }
    }
}

interface ComptrollerInterface {
    
    function isComptroller() external view returns (bool);

    

    function enterMarkets(address[] calldata cTokens) external returns (uint[] memory);
    function exitMarket(address cToken) external returns (uint);

    

    function mintAllowed(address cToken, address minter, uint mintAmount) external returns (uint);
    function mintVerify(address cToken, address minter, uint mintAmount, uint mintTokens) external;

    function redeemAllowed(address cToken, address redeemer, uint redeemTokens) external returns (uint);
    function redeemVerify(address cToken, address redeemer, uint redeemAmount, uint redeemTokens) external;

    function borrowAllowed(address cToken, address borrower, uint borrowAmount) external returns (uint);
    function borrowVerify(address cToken, address borrower, uint borrowAmount) external;

    function repayBorrowAllowed(
        address cToken,
        address payer,
        address borrower,
        uint repayAmount) external returns (uint);
    function repayBorrowVerify(
        address cToken,
        address payer,
        address borrower,
        uint repayAmount,
        uint borrowerIndex) external;

    function liquidateBorrowAllowed(
        address cTokenBorrowed,
        address cTokenCollateral,
        address liquidator,
        address borrower,
        uint repayAmount) external returns (uint);
    function liquidateBorrowVerify(
        address cTokenBorrowed,
        address cTokenCollateral,
        address liquidator,
        address borrower,
        uint repayAmount,
        uint seizeTokens) external;

    function seizeAllowed(
        address cTokenCollateral,
        address cTokenBorrowed,
        address liquidator,
        address borrower,
        uint seizeTokens) external returns (uint);
    function seizeVerify(
        address cTokenCollateral,
        address cTokenBorrowed,
        address liquidator,
        address borrower,
        uint seizeTokens) external;

    function transferAllowed(address cToken, address src, address dst, uint transferTokens) external returns (uint);
    function transferVerify(address cToken, address src, address dst, uint transferTokens) external;

    

    function liquidateCalculateSeizeTokens(
        address cTokenBorrowed,
        address cTokenCollateral,
        uint repayAmount) external view returns (uint, uint);
}

contract ComptrollerErrorReporter {
    enum Error {
        NO_ERROR,
        UNAUTHORIZED,
        COMPTROLLER_MISMATCH,
        INSUFFICIENT_SHORTFALL,
        INSUFFICIENT_LIQUIDITY,
        INVALID_CLOSE_FACTOR,
        INVALID_COLLATERAL_FACTOR,
        INVALID_LIQUIDATION_INCENTIVE,
        MARKET_NOT_ENTERED, 
        MARKET_NOT_LISTED,
        MARKET_ALREADY_LISTED,
        MATH_ERROR,
        NONZERO_BORROW_BALANCE,
        PRICE_ERROR,
        REJECTION,
        SNAPSHOT_ERROR,
        TOO_MANY_ASSETS,
        TOO_MUCH_REPAY
    }

    enum FailureInfo {
        ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
        ACCEPT_PENDING_IMPLEMENTATION_ADDRESS_CHECK,
        EXIT_MARKET_BALANCE_OWED,
        EXIT_MARKET_REJECTION,
        SET_CLOSE_FACTOR_OWNER_CHECK,
        SET_CLOSE_FACTOR_VALIDATION,
        SET_COLLATERAL_FACTOR_OWNER_CHECK,
        SET_COLLATERAL_FACTOR_NO_EXISTS,
        SET_COLLATERAL_FACTOR_VALIDATION,
        SET_COLLATERAL_FACTOR_WITHOUT_PRICE,
        SET_IMPLEMENTATION_OWNER_CHECK,
        SET_LIQUIDATION_INCENTIVE_OWNER_CHECK,
        SET_LIQUIDATION_INCENTIVE_VALIDATION,
        SET_MAX_ASSETS_OWNER_CHECK,
        SET_PENDING_ADMIN_OWNER_CHECK,
        SET_PENDING_IMPLEMENTATION_OWNER_CHECK,
        SET_PRICE_ORACLE_OWNER_CHECK,
        SUPPORT_MARKET_EXISTS,
        SUPPORT_MARKET_OWNER_CHECK,
        SET_PAUSE_GUARDIAN_OWNER_CHECK
    }

    
    event Failure(uint error, uint info, uint detail);

    
    function fail(Error err, FailureInfo info) internal returns (uint) {
        emit Failure(uint(err), uint(info), 0);

        return uint(err);
    }

    
    function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
        emit Failure(uint(err), uint(info), opaqueError);

        return uint(err);
    }
}

contract TokenErrorReporter {
    enum Error {
        NO_ERROR,
        UNAUTHORIZED,
        BAD_INPUT,
        COMPTROLLER_REJECTION,
        COMPTROLLER_CALCULATION_ERROR,
        INTEREST_RATE_MODEL_ERROR,
        INVALID_ACCOUNT_PAIR,
        INVALID_CLOSE_AMOUNT_REQUESTED,
        INVALID_COLLATERAL_FACTOR,
        MATH_ERROR,
        MARKET_NOT_FRESH,
        MARKET_NOT_LISTED,
        TOKEN_INSUFFICIENT_ALLOWANCE,
        TOKEN_INSUFFICIENT_BALANCE,
        TOKEN_INSUFFICIENT_CASH,
        TOKEN_TRANSFER_IN_FAILED,
        TOKEN_TRANSFER_OUT_FAILED
    }

    
    enum FailureInfo {
        ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
        ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED,
        ACCRUE_INTEREST_BORROW_RATE_CALCULATION_FAILED,
        ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED,
        ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED,
        ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED,
        ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED,
        BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
        BORROW_ACCRUE_INTEREST_FAILED,
        BORROW_CASH_NOT_AVAILABLE,
        BORROW_FRESHNESS_CHECK,
        BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
        BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
        BORROW_MARKET_NOT_LISTED,
        BORROW_COMPTROLLER_REJECTION,
        LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED,
        LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED,
        LIQUIDATE_COLLATERAL_FRESHNESS_CHECK,
        LIQUIDATE_COMPTROLLER_REJECTION,
        LIQUIDATE_COMPTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED,
        LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX,
        LIQUIDATE_CLOSE_AMOUNT_IS_ZERO,
        LIQUIDATE_FRESHNESS_CHECK,
        LIQUIDATE_LIQUIDATOR_IS_BORROWER,
        LIQUIDATE_REPAY_BORROW_FRESH_FAILED,
        LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED,
        LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED,
        LIQUIDATE_SEIZE_COMPTROLLER_REJECTION,
        LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER,
        LIQUIDATE_SEIZE_TOO_MUCH,
        MINT_ACCRUE_INTEREST_FAILED,
        MINT_COMPTROLLER_REJECTION,
        MINT_EXCHANGE_CALCULATION_FAILED,
        MINT_EXCHANGE_RATE_READ_FAILED,
        MINT_FRESHNESS_CHECK,
        MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
        MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
        MINT_TRANSFER_IN_FAILED,
        MINT_TRANSFER_IN_NOT_POSSIBLE,
        REDEEM_ACCRUE_INTEREST_FAILED,
        REDEEM_COMPTROLLER_REJECTION,
        REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED,
        REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED,
        REDEEM_EXCHANGE_RATE_READ_FAILED,
        REDEEM_FRESHNESS_CHECK,
        REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
        REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
        REDEEM_TRANSFER_OUT_NOT_POSSIBLE,
        REDUCE_RESERVES_ACCRUE_INTEREST_FAILED,
        REDUCE_RESERVES_ADMIN_CHECK,
        REDUCE_RESERVES_CASH_NOT_AVAILABLE,
        REDUCE_RESERVES_FRESH_CHECK,
        REDUCE_RESERVES_VALIDATION,
        REPAY_BEHALF_ACCRUE_INTEREST_FAILED,
        REPAY_BORROW_ACCRUE_INTEREST_FAILED,
        REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
        REPAY_BORROW_COMPTROLLER_REJECTION,
        REPAY_BORROW_FRESHNESS_CHECK,
        REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
        REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
        REPAY_BORROW_TRANSFER_IN_NOT_POSSIBLE,
        SET_COLLATERAL_FACTOR_OWNER_CHECK,
        SET_COLLATERAL_FACTOR_VALIDATION,
        SET_COMPTROLLER_OWNER_CHECK,
        SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED,
        SET_INTEREST_RATE_MODEL_FRESH_CHECK,
        SET_INTEREST_RATE_MODEL_OWNER_CHECK,
        SET_MAX_ASSETS_OWNER_CHECK,
        SET_ORACLE_MARKET_NOT_LISTED,
        SET_PENDING_ADMIN_OWNER_CHECK,
        SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED,
        SET_RESERVE_FACTOR_ADMIN_CHECK,
        SET_RESERVE_FACTOR_FRESH_CHECK,
        SET_RESERVE_FACTOR_BOUNDS_CHECK,
        TRANSFER_COMPTROLLER_REJECTION,
        TRANSFER_NOT_ALLOWED,
        TRANSFER_NOT_ENOUGH,
        TRANSFER_TOO_MUCH
    }

    
    event Failure(uint error, uint info, uint detail);

    
    function fail(Error err, FailureInfo info) internal returns (uint) {
        emit Failure(uint(err), uint(info), 0);

        return uint(err);
    }

    
    function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
        emit Failure(uint(err), uint(info), opaqueError);

        return uint(err);
    }
}

contract CarefulMath {

    
    enum MathError {
        NO_ERROR,
        DIVISION_BY_ZERO,
        INTEGER_OVERFLOW,
        INTEGER_UNDERFLOW
    }

    
    function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
        if (a == 0) {
            return (MathError.NO_ERROR, 0);
        }

        uint c = a * b;

        if (c / a != b) {
            return (MathError.INTEGER_OVERFLOW, 0);
        } else {
            return (MathError.NO_ERROR, c);
        }
    }

    
    function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
        if (b == 0) {
            return (MathError.DIVISION_BY_ZERO, 0);
        }

        return (MathError.NO_ERROR, a / b);
    }

    
    function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
        if (b <= a) {
            return (MathError.NO_ERROR, a - b);
        } else {
            return (MathError.INTEGER_UNDERFLOW, 0);
        }
    }

    
    function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
        uint c = a + b;

        if (c >= a) {
            return (MathError.NO_ERROR, c);
        } else {
            return (MathError.INTEGER_OVERFLOW, 0);
        }
    }

    
    function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
        (MathError err0, uint sum) = addUInt(a, b);

        if (err0 != MathError.NO_ERROR) {
            return (err0, 0);
        }

        return subUInt(sum, c);
    }
}

contract Exponential is CarefulMath {
    uint constant expScale = 1e18;
    uint constant halfExpScale = expScale/2;
    uint constant mantissaOne = expScale;

    struct Exp {
        uint mantissa;
    }

    
    function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        (MathError err1, uint rational) = divUInt(scaledNumerator, denom);
        if (err1 != MathError.NO_ERROR) {
            return (err1, Exp({mantissa: 0}));
        }

        return (MathError.NO_ERROR, Exp({mantissa: rational}));
    }

    
    function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
        (MathError error, uint result) = addUInt(a.mantissa, b.mantissa);

        return (error, Exp({mantissa: result}));
    }

    
    function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
        (MathError error, uint result) = subUInt(a.mantissa, b.mantissa);

        return (error, Exp({mantissa: result}));
    }

    
    function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
    }

    
    function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
        (MathError err, Exp memory product) = mulScalar(a, scalar);
        if (err != MathError.NO_ERROR) {
            return (err, 0);
        }

        return (MathError.NO_ERROR, truncate(product));
    }

    
    function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
        (MathError err, Exp memory product) = mulScalar(a, scalar);
        if (err != MathError.NO_ERROR) {
            return (err, 0);
        }

        return addUInt(truncate(product), addend);
    }

    
    function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
    }

    
    function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
        
        (MathError err0, uint numerator) = mulUInt(expScale, scalar);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }
        return getExp(numerator, divisor.mantissa);
    }

    
    function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
        (MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
        if (err != MathError.NO_ERROR) {
            return (err, 0);
        }

        return (MathError.NO_ERROR, truncate(fraction));
    }

    
    function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {

        (MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        
        
        
        (MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
        if (err1 != MathError.NO_ERROR) {
            return (err1, Exp({mantissa: 0}));
        }

        (MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
        
        assert(err2 == MathError.NO_ERROR);

        return (MathError.NO_ERROR, Exp({mantissa: product}));
    }

    
    function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
        return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
    }

    
    function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
        (MathError err, Exp memory ab) = mulExp(a, b);
        if (err != MathError.NO_ERROR) {
            return (err, ab);
        }
        return mulExp(ab, c);
    }

    
    function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
        return getExp(a.mantissa, b.mantissa);
    }

    
    function truncate(Exp memory exp) pure internal returns (uint) {
        
        return exp.mantissa / expScale;
    }

    
    function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
        return left.mantissa < right.mantissa;
    }

    
    function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
        return left.mantissa <= right.mantissa;
    }

    
    function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
        return left.mantissa > right.mantissa;
    }

    
    function isZeroExp(Exp memory value) pure internal returns (bool) {
        return value.mantissa == 0;
    }
}

interface EIP20Interface {

    
    function totalSupply() external view returns (uint256);

    
    function balanceOf(address owner) external view returns (uint256 balance);

    
    function transfer(address dst, uint256 amount) external returns (bool success);

    
    function transferFrom(address src, address dst, uint256 amount) external returns (bool success);

    
    function approve(address spender, uint256 amount) external returns (bool success);

    
    function allowance(address owner, address spender) external view returns (uint256 remaining);

    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
}

interface EIP20NonStandardInterface {

    
    function totalSupply() external view returns (uint256);

    
    function balanceOf(address owner) external view returns (uint256 balance);

    
    
    
    
    

    
    function transfer(address dst, uint256 amount) external;

    
    
    
    
    

    
    function transferFrom(address src, address dst, uint256 amount) external;

    
    function approve(address spender, uint256 amount) external returns (bool success);

    
    function allowance(address owner, address spender) external view returns (uint256 remaining);

    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
}

contract ReentrancyGuard {
    
    uint256 private _guardCounter;

    constructor () internal {
        
        
        _guardCounter = 1;
    }

    
    modifier nonReentrant() {
        _guardCounter += 1;
        uint256 localCounter = _guardCounter;
        _;
        require(localCounter == _guardCounter, "re-entered");
    }
}

interface InterestRateModel {
    
    function getBorrowRate(uint cash, uint borrows, uint reserves) external view returns (uint, uint);

    
    function isInterestRateModel() external view returns (bool);
}

contract CToken is EIP20Interface, Exponential, TokenErrorReporter, ReentrancyGuard {
    
    bool public constant isCToken = true;

    
    string public name;

    
    string public symbol;

    
    uint8 public decimals;

    

    uint internal constant borrowRateMaxMantissa = 0.0005e16;

    
    uint internal constant reserveFactorMaxMantissa = 1e18;

    
    address payable public admin;

    
    address payable public pendingAdmin;

    
    ComptrollerInterface public comptroller;

    
    InterestRateModel public interestRateModel;

    
    uint public initialExchangeRateMantissa;

    
    uint public reserveFactorMantissa;

    
    uint public accrualBlockNumber;

    
    uint public borrowIndex;

    
    uint public totalBorrows;

    
    uint public totalReserves;

    
    uint256 public totalSupply;

    
    mapping (address => uint256) internal accountTokens;

    
    mapping (address => mapping (address => uint256)) internal transferAllowances;

    
    struct BorrowSnapshot {
        uint principal;
        uint interestIndex;
    }

    
    mapping(address => BorrowSnapshot) internal accountBorrows;


    

    
    event AccrueInterest(uint interestAccumulated, uint borrowIndex, uint totalBorrows);

    
    event Mint(address minter, uint mintAmount, uint mintTokens);

    
    event Redeem(address redeemer, uint redeemAmount, uint redeemTokens);

    
    event Borrow(address borrower, uint borrowAmount, uint accountBorrows, uint totalBorrows);

    
    event RepayBorrow(address payer, address borrower, uint repayAmount, uint accountBorrows, uint totalBorrows);

    
    event LiquidateBorrow(address liquidator, address borrower, uint repayAmount, address cTokenCollateral, uint seizeTokens);


    

    
    event NewPendingAdmin(address oldPendingAdmin, address newPendingAdmin);

    
    event NewAdmin(address oldAdmin, address newAdmin);

    
    event NewComptroller(ComptrollerInterface oldComptroller, ComptrollerInterface newComptroller);

    
    event NewMarketInterestRateModel(InterestRateModel oldInterestRateModel, InterestRateModel newInterestRateModel);

    
    event NewReserveFactor(uint oldReserveFactorMantissa, uint newReserveFactorMantissa);

    
    event ReservesReduced(address admin, uint reduceAmount, uint newTotalReserves);


    
    constructor(ComptrollerInterface comptroller_,
                InterestRateModel interestRateModel_,
                uint initialExchangeRateMantissa_,
                string memory name_,
                string memory symbol_,
                uint8 decimals_,
                address payable admin_) internal {
        
        initialExchangeRateMantissa = initialExchangeRateMantissa_;
        require(initialExchangeRateMantissa > 0, "Initial exchange rate must be greater than zero.");

        
        admin = msg.sender;
        
        uint err = _setComptroller(comptroller_);
        require(err == uint(Error.NO_ERROR), "Setting comptroller failed");

        
        accrualBlockNumber = getBlockNumber();
        borrowIndex = mantissaOne;

        
        err = _setInterestRateModelFresh(interestRateModel_);
        require(err == uint(Error.NO_ERROR), "Setting interest rate model failed");

        name = name_;
        symbol = symbol_;
        decimals = decimals_;

        
        admin = admin_;
    }

    
    function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) {
        
        uint allowed = comptroller.transferAllowed(address(this), src, dst, tokens);
        if (allowed != 0) {
            return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.TRANSFER_COMPTROLLER_REJECTION, allowed);
        }

        
        if (src == dst) {
            return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED);
        }

        
        uint startingAllowance = 0;
        if (spender == src) {
            startingAllowance = uint(-1);
        } else {
            startingAllowance = transferAllowances[src][spender];
        }

        
        MathError mathErr;
        uint allowanceNew;
        uint srcTokensNew;
        uint dstTokensNew;

        (mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
        if (mathErr != MathError.NO_ERROR) {
            return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED);
        }

        (mathErr, srcTokensNew) = subUInt(accountTokens[src], tokens);
        if (mathErr != MathError.NO_ERROR) {
            return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH);
        }

        (mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
        if (mathErr != MathError.NO_ERROR) {
            return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH);
        }

        
        
        

        accountTokens[src] = srcTokensNew;
        accountTokens[dst] = dstTokensNew;

        
        if (startingAllowance != uint(-1)) {
            transferAllowances[src][spender] = allowanceNew;
        }

        
        emit Transfer(src, dst, tokens);

        comptroller.transferVerify(address(this), src, dst, tokens);

        return uint(Error.NO_ERROR);
    }

    
    function transfer(address dst, uint256 amount) external nonReentrant returns (bool) {
        return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR);
    }

    
    function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) {
        return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR);
    }

    
    function approve(address spender, uint256 amount) external returns (bool) {
        address src = msg.sender;
        transferAllowances[src][spender] = amount;
        emit Approval(src, spender, amount);
        return true;
    }

    
    function allowance(address owner, address spender) external view returns (uint256) {
        return transferAllowances[owner][spender];
    }

    
    function balanceOf(address owner) external view returns (uint256) {
        return accountTokens[owner];
    }

    
    function balanceOfUnderlying(address owner) external returns (uint) {
        Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
        (MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]);
        require(mErr == MathError.NO_ERROR);
        return balance;
    }

    
    function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) {
        uint cTokenBalance = accountTokens[account];
        uint borrowBalance;
        uint exchangeRateMantissa;

        MathError mErr;

        (mErr, borrowBalance) = borrowBalanceStoredInternal(account);
        if (mErr != MathError.NO_ERROR) {
            return (uint(Error.MATH_ERROR), 0, 0, 0);
        }

        (mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
        if (mErr != MathError.NO_ERROR) {
            return (uint(Error.MATH_ERROR), 0, 0, 0);
        }

        return (uint(Error.NO_ERROR), cTokenBalance, borrowBalance, exchangeRateMantissa);
    }

    
    function getBlockNumber() internal view returns (uint) {
        return block.number;
    }

    
    function borrowRatePerBlock() external view returns (uint) {
        (uint opaqueErr, uint borrowRateMantissa) = interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
        require(opaqueErr == 0, "borrowRatePerBlock: interestRateModel.borrowRate failed"); 
        return borrowRateMantissa;
    }

    
    function supplyRatePerBlock() external view returns (uint) {
        
        uint exchangeRateMantissa = exchangeRateStored();

        (uint e0, uint borrowRateMantissa) = interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
        require(e0 == 0, "supplyRatePerBlock: calculating borrowRate failed"); 

        (MathError e1, Exp memory underlying) = mulScalar(Exp({mantissa: exchangeRateMantissa}), totalSupply);
        require(e1 == MathError.NO_ERROR, "supplyRatePerBlock: calculating underlying failed");

        (MathError e2, Exp memory borrowsPer) = divScalarByExp(totalBorrows, underlying);
        require(e2 == MathError.NO_ERROR, "supplyRatePerBlock: calculating borrowsPer failed");

        (MathError e3, Exp memory oneMinusReserveFactor) = subExp(Exp({mantissa: mantissaOne}), Exp({mantissa: reserveFactorMantissa}));
        require(e3 == MathError.NO_ERROR, "supplyRatePerBlock: calculating oneMinusReserveFactor failed");

        (MathError e4, Exp memory supplyRate) = mulExp3(Exp({mantissa: borrowRateMantissa}), oneMinusReserveFactor, borrowsPer);
        require(e4 == MathError.NO_ERROR, "supplyRatePerBlock: calculating supplyRate failed");

        return supplyRate.mantissa;
    }

    
    function totalBorrowsCurrent() external nonReentrant returns (uint) {
        require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
        return totalBorrows;
    }

    
    function borrowBalanceCurrent(address account) external nonReentrant returns (uint) {
        require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
        return borrowBalanceStored(account);
    }

    
    function borrowBalanceStored(address account) public view returns (uint) {
        (MathError err, uint result) = borrowBalanceStoredInternal(account);
        require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed");
        return result;
    }

    
    function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) {
        
        MathError mathErr;
        uint principalTimesIndex;
        uint result;

        
        BorrowSnapshot storage borrowSnapshot = accountBorrows[account];

        
        if (borrowSnapshot.principal == 0) {
            return (MathError.NO_ERROR, 0);
        }

        
        (mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex);
        if (mathErr != MathError.NO_ERROR) {
            return (mathErr, 0);
        }

        (mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex);
        if (mathErr != MathError.NO_ERROR) {
            return (mathErr, 0);
        }

        return (MathError.NO_ERROR, result);
    }

    
    function exchangeRateCurrent() public nonReentrant returns (uint) {
        require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed");
        return exchangeRateStored();
    }

    
    function exchangeRateStored() public view returns (uint) {
        (MathError err, uint result) = exchangeRateStoredInternal();
        require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed");
        return result;
    }

    
    function exchangeRateStoredInternal() internal view returns (MathError, uint) {
        if (totalSupply == 0) {
            
            return (MathError.NO_ERROR, initialExchangeRateMantissa);
        } else {
            
            uint totalCash = getCashPrior();
            uint cashPlusBorrowsMinusReserves;
            Exp memory exchangeRate;
            MathError mathErr;

            (mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves);
            if (mathErr != MathError.NO_ERROR) {
                return (mathErr, 0);
            }

            (mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, totalSupply);
            if (mathErr != MathError.NO_ERROR) {
                return (mathErr, 0);
            }

            return (MathError.NO_ERROR, exchangeRate.mantissa);
        }
    }

    
    function getCash() external view returns (uint) {
        return getCashPrior();
    }

    struct AccrueInterestLocalVars {
        MathError mathErr;
        uint opaqueErr;
        uint borrowRateMantissa;
        uint currentBlockNumber;
        uint blockDelta;

        Exp simpleInterestFactor;

        uint interestAccumulated;
        uint totalBorrowsNew;
        uint totalReservesNew;
        uint borrowIndexNew;
    }

    
    function accrueInterest() public returns (uint) {
        AccrueInterestLocalVars memory vars;

        
        (vars.opaqueErr, vars.borrowRateMantissa) = interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves);
        require(vars.borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high");
        if (vars.opaqueErr != 0) {
            return failOpaque(Error.INTEREST_RATE_MODEL_ERROR, FailureInfo.ACCRUE_INTEREST_BORROW_RATE_CALCULATION_FAILED, vars.opaqueErr);
        }

        
        vars.currentBlockNumber = getBlockNumber();

        
        (vars.mathErr, vars.blockDelta) = subUInt(vars.currentBlockNumber, accrualBlockNumber);
        assert(vars.mathErr == MathError.NO_ERROR); 

        
        (vars.mathErr, vars.simpleInterestFactor) = mulScalar(Exp({mantissa: vars.borrowRateMantissa}), vars.blockDelta);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.interestAccumulated) = mulScalarTruncate(vars.simpleInterestFactor, totalBorrows);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.totalBorrowsNew) = addUInt(vars.interestAccumulated, totalBorrows);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), vars.interestAccumulated, totalReserves);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.borrowIndexNew) = mulScalarTruncateAddUInt(vars.simpleInterestFactor, borrowIndex, borrowIndex);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(vars.mathErr));
        }

        
        
        

        
        accrualBlockNumber = vars.currentBlockNumber;
        borrowIndex = vars.borrowIndexNew;
        totalBorrows = vars.totalBorrowsNew;
        totalReserves = vars.totalReservesNew;

        
        emit AccrueInterest(vars.interestAccumulated, vars.borrowIndexNew, totalBorrows);

        return uint(Error.NO_ERROR);
    }

    
    function mintInternal(uint mintAmount) internal nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED);
        }
        
        return mintFresh(msg.sender, mintAmount);
    }

    struct MintLocalVars {
        Error err;
        MathError mathErr;
        uint exchangeRateMantissa;
        uint mintTokens;
        uint totalSupplyNew;
        uint accountTokensNew;
    }

    
    function mintFresh(address minter, uint mintAmount) internal returns (uint) {
        
        uint allowed = comptroller.mintAllowed(address(this), minter, mintAmount);
        if (allowed != 0) {
            return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.MINT_COMPTROLLER_REJECTION, allowed);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK);
        }

        MintLocalVars memory vars;

        
        vars.err = checkTransferIn(minter, mintAmount);
        if (vars.err != Error.NO_ERROR) {
            return fail(vars.err, FailureInfo.MINT_TRANSFER_IN_NOT_POSSIBLE);
        }

        
        (vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(mintAmount, Exp({mantissa: vars.exchangeRateMantissa}));
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        
        (vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        
        
        

        
        vars.err = doTransferIn(minter, mintAmount);
        if (vars.err != Error.NO_ERROR) {
            return fail(vars.err, FailureInfo.MINT_TRANSFER_IN_FAILED);
        }

        
        totalSupply = vars.totalSupplyNew;
        accountTokens[minter] = vars.accountTokensNew;

        
        emit Mint(minter, mintAmount, vars.mintTokens);
        emit Transfer(address(this), minter, vars.mintTokens);

        
        comptroller.mintVerify(address(this), minter, mintAmount, vars.mintTokens);

        return uint(Error.NO_ERROR);
    }

    
    function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
        }
        
        return redeemFresh(msg.sender, redeemTokens, 0);
    }

    
    function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
        }
        
        return redeemFresh(msg.sender, 0, redeemAmount);
    }

    struct RedeemLocalVars {
        Error err;
        MathError mathErr;
        uint exchangeRateMantissa;
        uint redeemTokens;
        uint redeemAmount;
        uint totalSupplyNew;
        uint accountTokensNew;
    }

    
    function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) {
        require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero");

        RedeemLocalVars memory vars;

        
        (vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal();
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr));
        }

        
        if (redeemTokensIn > 0) {
            
            vars.redeemTokens = redeemTokensIn;

            (vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn);
            if (vars.mathErr != MathError.NO_ERROR) {
                return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr));
            }
        } else {
            

            (vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa}));
            if (vars.mathErr != MathError.NO_ERROR) {
                return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr));
            }

            vars.redeemAmount = redeemAmountIn;
        }

        
        uint allowed = comptroller.redeemAllowed(address(this), redeemer, vars.redeemTokens);
        if (allowed != 0) {
            return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.REDEEM_COMPTROLLER_REJECTION, allowed);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK);
        }

        
        (vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        
        if (getCashPrior() < vars.redeemAmount) {
            return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE);
        }

        
        
        

        
        vars.err = doTransferOut(redeemer, vars.redeemAmount);
        require(vars.err == Error.NO_ERROR, "redeem transfer out failed");

        
        totalSupply = vars.totalSupplyNew;
        accountTokens[redeemer] = vars.accountTokensNew;

        
        emit Transfer(redeemer, address(this), vars.redeemTokens);
        emit Redeem(redeemer, vars.redeemAmount, vars.redeemTokens);

        
        comptroller.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens);

        return uint(Error.NO_ERROR);
    }

    
    function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
        }
        
        return borrowFresh(msg.sender, borrowAmount);
    }

    struct BorrowLocalVars {
        Error err;
        MathError mathErr;
        uint accountBorrows;
        uint accountBorrowsNew;
        uint totalBorrowsNew;
    }

    
    function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) {
        
        uint allowed = comptroller.borrowAllowed(address(this), borrower, borrowAmount);
        if (allowed != 0) {
            return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.BORROW_COMPTROLLER_REJECTION, allowed);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK);
        }

        
        if (getCashPrior() < borrowAmount) {
            return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE);
        }

        BorrowLocalVars memory vars;

        
        (vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        
        
        

        
        vars.err = doTransferOut(borrower, borrowAmount);
        require(vars.err == Error.NO_ERROR, "borrow transfer out failed");

        
        accountBorrows[borrower].principal = vars.accountBorrowsNew;
        accountBorrows[borrower].interestIndex = borrowIndex;
        totalBorrows = vars.totalBorrowsNew;

        
        emit Borrow(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);

        
        comptroller.borrowVerify(address(this), borrower, borrowAmount);

        return uint(Error.NO_ERROR);
    }

    
    function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED);
        }
        
        return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
    }

    
    function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED);
        }
        
        return repayBorrowFresh(msg.sender, borrower, repayAmount);
    }

    struct RepayBorrowLocalVars {
        Error err;
        MathError mathErr;
        uint repayAmount;
        uint borrowerIndex;
        uint accountBorrows;
        uint accountBorrowsNew;
        uint totalBorrowsNew;
    }

    
    function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint) {
        
        uint allowed = comptroller.repayBorrowAllowed(address(this), payer, borrower, repayAmount);
        if (allowed != 0) {
            return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.REPAY_BORROW_COMPTROLLER_REJECTION, allowed);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK);
        }

        RepayBorrowLocalVars memory vars;

        
        vars.borrowerIndex = accountBorrows[borrower].interestIndex;

        
        (vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        
        if (repayAmount == uint(-1)) {
            vars.repayAmount = vars.accountBorrows;
        } else {
            vars.repayAmount = repayAmount;
        }

        
        vars.err = checkTransferIn(payer, vars.repayAmount);
        if (vars.err != Error.NO_ERROR) {
            return fail(vars.err, FailureInfo.REPAY_BORROW_TRANSFER_IN_NOT_POSSIBLE);
        }

        
        (vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.repayAmount);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        (vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.repayAmount);
        if (vars.mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr));
        }

        
        
        

        
        vars.err = doTransferIn(payer, vars.repayAmount);
        require(vars.err == Error.NO_ERROR, "repay borrow transfer in failed");

        
        accountBorrows[borrower].principal = vars.accountBorrowsNew;
        accountBorrows[borrower].interestIndex = borrowIndex;
        totalBorrows = vars.totalBorrowsNew;

        
        emit RepayBorrow(payer, borrower, vars.repayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew);

        
        comptroller.repayBorrowVerify(address(this), payer, borrower, vars.repayAmount, vars.borrowerIndex);

        return uint(Error.NO_ERROR);
    }

    
    function liquidateBorrowInternal(address borrower, uint repayAmount, CToken cTokenCollateral) internal nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED);
        }

        error = cTokenCollateral.accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED);
        }

        
        return liquidateBorrowFresh(msg.sender, borrower, repayAmount, cTokenCollateral);
    }

    
    function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, CToken cTokenCollateral) internal returns (uint) {
        
        uint allowed = comptroller.liquidateBorrowAllowed(address(this), address(cTokenCollateral), liquidator, borrower, repayAmount);
        if (allowed != 0) {
            return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.LIQUIDATE_COMPTROLLER_REJECTION, allowed);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK);
        }

        
        if (cTokenCollateral.accrualBlockNumber() != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK);
        }

        
        if (borrower == liquidator) {
            return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER);
        }

        
        if (repayAmount == 0) {
            return fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO);
        }

        
        if (repayAmount == uint(-1)) {
            return fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX);
        }

        
        (uint amountSeizeError, uint seizeTokens) = comptroller.liquidateCalculateSeizeTokens(address(this), address(cTokenCollateral), repayAmount);
        if (amountSeizeError != 0) {
            return failOpaque(Error.COMPTROLLER_CALCULATION_ERROR, FailureInfo.LIQUIDATE_COMPTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED, amountSeizeError);
        }

        
        if (seizeTokens > cTokenCollateral.balanceOf(borrower)) {
            return fail(Error.TOKEN_INSUFFICIENT_BALANCE, FailureInfo.LIQUIDATE_SEIZE_TOO_MUCH);
        }

        
        uint repayBorrowError = repayBorrowFresh(liquidator, borrower, repayAmount);
        if (repayBorrowError != uint(Error.NO_ERROR)) {
            return fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED);
        }

        
        uint seizeError = cTokenCollateral.seize(liquidator, borrower, seizeTokens);
        require(seizeError == uint(Error.NO_ERROR), "token seizure failed");

        
        emit LiquidateBorrow(liquidator, borrower, repayAmount, address(cTokenCollateral), seizeTokens);

        
        comptroller.liquidateBorrowVerify(address(this), address(cTokenCollateral), liquidator, borrower, repayAmount, seizeTokens);

        return uint(Error.NO_ERROR);
    }

    
    function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) {
        
        uint allowed = comptroller.seizeAllowed(address(this), msg.sender, liquidator, borrower, seizeTokens);
        if (allowed != 0) {
            return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_COMPTROLLER_REJECTION, allowed);
        }

        
        if (borrower == liquidator) {
            return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER);
        }

        MathError mathErr;
        uint borrowerTokensNew;
        uint liquidatorTokensNew;

        
        (mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens);
        if (mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr));
        }

        (mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens);
        if (mathErr != MathError.NO_ERROR) {
            return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr));
        }

        
        
        

        
        accountTokens[borrower] = borrowerTokensNew;
        accountTokens[liquidator] = liquidatorTokensNew;

        
        emit Transfer(borrower, liquidator, seizeTokens);

        
        comptroller.seizeVerify(address(this), msg.sender, liquidator, borrower, seizeTokens);

        return uint(Error.NO_ERROR);
    }


    

    
    function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) {
        
        if (msg.sender != admin) {
            return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
        }

        
        address oldPendingAdmin = pendingAdmin;

        
        pendingAdmin = newPendingAdmin;

        
        emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin);

        return uint(Error.NO_ERROR);
    }

    
    function _acceptAdmin() external returns (uint) {
        
        if (msg.sender != pendingAdmin || msg.sender == address(0)) {
            return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
        }

        
        address oldAdmin = admin;
        address oldPendingAdmin = pendingAdmin;

        
        admin = pendingAdmin;

        
        pendingAdmin = address(0);

        emit NewAdmin(oldAdmin, admin);
        emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);

        return uint(Error.NO_ERROR);
    }

    
    function _setComptroller(ComptrollerInterface newComptroller) public returns (uint) {
        
        if (msg.sender != admin) {
            return fail(Error.UNAUTHORIZED, FailureInfo.SET_COMPTROLLER_OWNER_CHECK);
        }

        ComptrollerInterface oldComptroller = comptroller;
        
        require(newComptroller.isComptroller(), "marker method returned false");

        
        comptroller = newComptroller;

        
        emit NewComptroller(oldComptroller, newComptroller);

        return uint(Error.NO_ERROR);
    }

    
    function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED);
        }
        
        return _setReserveFactorFresh(newReserveFactorMantissa);
    }

    
    function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) {
        
        if (msg.sender != admin) {
            return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK);
        }

        
        if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
            return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK);
        }

        uint oldReserveFactorMantissa = reserveFactorMantissa;
        reserveFactorMantissa = newReserveFactorMantissa;

        emit NewReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa);

        return uint(Error.NO_ERROR);
    }

    
    function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED);
        }
        
        return _reduceReservesFresh(reduceAmount);
    }

    
    function _reduceReservesFresh(uint reduceAmount) internal returns (uint) {
        Error err;
        
        uint totalReservesNew;

        
        if (msg.sender != admin) {
            return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK);
        }

        
        if (getCashPrior() < reduceAmount) {
            return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE);
        }

        
        if (reduceAmount > totalReserves) {
            return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
        }

        
        
        

        totalReservesNew = totalReserves - reduceAmount;
        
        require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow");

        
        totalReserves = totalReservesNew;

        
        err = doTransferOut(admin, reduceAmount);
        
        require(err == Error.NO_ERROR, "reduce reserves transfer out failed");

        emit ReservesReduced(admin, reduceAmount, totalReservesNew);

        return uint(Error.NO_ERROR);
    }

    
    function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) {
        uint error = accrueInterest();
        if (error != uint(Error.NO_ERROR)) {
            
            return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED);
        }
        
        return _setInterestRateModelFresh(newInterestRateModel);
    }

    
    function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) {

        
        InterestRateModel oldInterestRateModel;

        
        if (msg.sender != admin) {
            return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
        }

        
        if (accrualBlockNumber != getBlockNumber()) {
            return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK);
        }

        
        oldInterestRateModel = interestRateModel;

        
        require(newInterestRateModel.isInterestRateModel(), "marker method returned false");

        
        interestRateModel = newInterestRateModel;

        
        emit NewMarketInterestRateModel(oldInterestRateModel, newInterestRateModel);

        return uint(Error.NO_ERROR);
    }

    

    
    function getCashPrior() internal view returns (uint);

    
    function checkTransferIn(address from, uint amount) internal view returns (Error);

    
    function doTransferIn(address from, uint amount) internal returns (Error);

    
    function doTransferOut(address payable to, uint amount) internal returns (Error);
}

contract CErc20 is CToken {

    
    address public underlying;

    
    constructor(address underlying_,
                ComptrollerInterface comptroller_,
                InterestRateModel interestRateModel_,
                uint initialExchangeRateMantissa_,
                string memory name_,
                string memory symbol_,
                uint8 decimals_,
                address payable admin_) public
    CToken(comptroller_, interestRateModel_, initialExchangeRateMantissa_, name_, symbol_, decimals_, admin_) {
        
        underlying = underlying_;
        EIP20Interface(underlying).totalSupply(); 
    }

    

    
    function mint(uint mintAmount) external returns (uint) {
        return mintInternal(mintAmount);
    }

    
    function redeem(uint redeemTokens) external returns (uint) {
        return redeemInternal(redeemTokens);
    }

    
    function redeemUnderlying(uint redeemAmount) external returns (uint) {
        return redeemUnderlyingInternal(redeemAmount);
    }

    
    function borrow(uint borrowAmount) external returns (uint) {
        return borrowInternal(borrowAmount);
    }

    
    function repayBorrow(uint repayAmount) external returns (uint) {
        return repayBorrowInternal(repayAmount);
    }

    
    function repayBorrowBehalf(address borrower, uint repayAmount) external returns (uint) {
        return repayBorrowBehalfInternal(borrower, repayAmount);
    }

    
    function liquidateBorrow(address borrower, uint repayAmount, CToken cTokenCollateral) external returns (uint) {
        return liquidateBorrowInternal(borrower, repayAmount, cTokenCollateral);
    }

    

    
    function getCashPrior() internal view returns (uint) {
        EIP20Interface token = EIP20Interface(underlying);
        return token.balanceOf(address(this));
    }

    
    function checkTransferIn(address from, uint amount) internal view returns (Error) {
        EIP20Interface token = EIP20Interface(underlying);

        if (token.allowance(from, address(this)) < amount) {
            return Error.TOKEN_INSUFFICIENT_ALLOWANCE;
        }

        if (token.balanceOf(from) < amount) {
            return Error.TOKEN_INSUFFICIENT_BALANCE;
        }

        return Error.NO_ERROR;
    }

    
    function doTransferIn(address from, uint amount) internal returns (Error) {
        EIP20NonStandardInterface token = EIP20NonStandardInterface(underlying);
        bool result;

        token.transferFrom(from, address(this), amount);

        
        assembly {
            switch returndatasize()
                case 0 {                      
                    result := not(0)          
                }
                case 32 {                     
                    returndatacopy(0, 0, 32)
                    result := mload(0)        
                }
                default {                     
                    revert(0, 0)
                }
        }

        if (!result) {
            return Error.TOKEN_TRANSFER_IN_FAILED;
        }

        return Error.NO_ERROR;
    }

    
    function doTransferOut(address payable to, uint amount) internal returns (Error) {
        EIP20NonStandardInterface token = EIP20NonStandardInterface(underlying);
        bool result;

        token.transfer(to, amount);

        
        assembly {
            switch returndatasize()
                case 0 {                      
                    result := not(0)          
                }
                case 32 {                     
                    returndatacopy(0, 0, 32)
                    result := mload(0)        
                }
                default {                     
                    revert(0, 0)
                }
        }

        if (!result) {
            return Error.TOKEN_TRANSFER_OUT_FAILED;
        }

        return Error.NO_ERROR;
    }
}

contract CEther is CToken {
    
    constructor(ComptrollerInterface comptroller_,
                InterestRateModel interestRateModel_,
                uint initialExchangeRateMantissa_,
                string memory name_,
                string memory symbol_,
                uint8 decimals_,
                address payable admin_) public
    CToken(comptroller_, interestRateModel_, initialExchangeRateMantissa_, name_, symbol_, decimals_, admin_) {}

    

    
    function mint() external payable {
        requireNoError(mintInternal(msg.value), "mint failed");
    }

    
    function redeem(uint redeemTokens) external returns (uint) {
        return redeemInternal(redeemTokens);
    }

    
    function redeemUnderlying(uint redeemAmount) external returns (uint) {
        return redeemUnderlyingInternal(redeemAmount);
    }

    
    function borrow(uint borrowAmount) external returns (uint) {
        return borrowInternal(borrowAmount);
    }

    
    function repayBorrow() external payable {
        requireNoError(repayBorrowInternal(msg.value), "repayBorrow failed");
    }

    
    function repayBorrowBehalf(address borrower) external payable {
        requireNoError(repayBorrowBehalfInternal(borrower, msg.value), "repayBorrowBehalf failed");
    }

    
    function liquidateBorrow(address borrower, CToken cTokenCollateral) external payable {
        requireNoError(liquidateBorrowInternal(borrower, msg.value, cTokenCollateral), "liquidateBorrow failed");
    }

    
    function () external payable {
        requireNoError(mintInternal(msg.value), "mint failed");
    }

    

    
    function getCashPrior() internal view returns (uint) {
        (MathError err, uint startingBalance) = subUInt(address(this).balance, msg.value);
        require(err == MathError.NO_ERROR);
        return startingBalance;
    }

    
    function checkTransferIn(address from, uint amount) internal view returns (Error) {
        
        require(msg.sender == from, "sender mismatch");
        require(msg.value == amount, "value mismatch");
        return Error.NO_ERROR;
    }

    
    function doTransferIn(address from, uint amount) internal returns (Error) {
        
        require(msg.sender == from, "sender mismatch");
        require(msg.value == amount, "value mismatch");
        return Error.NO_ERROR;
    }

    function doTransferOut(address payable to, uint amount) internal returns (Error) {
        
        to.transfer(amount);
        return Error.NO_ERROR;
    }

    function requireNoError(uint errCode, string memory message) internal pure {
        if (errCode == uint(Error.NO_ERROR)) {
            return;
        }

        bytes memory fullMessage = new bytes(bytes(message).length + 5);
        uint i;

        for (i = 0; i < bytes(message).length; i++) {
            fullMessage[i] = bytes(message)[i];
        }

        fullMessage[i+0] = byte(uint8(32));
        fullMessage[i+1] = byte(uint8(40));
        fullMessage[i+2] = byte(uint8(48 + ( errCode / 10 )));
        fullMessage[i+3] = byte(uint8(48 + ( errCode % 10 )));
        fullMessage[i+4] = byte(uint8(41));

        require(errCode == uint(Error.NO_ERROR), string(fullMessage));
    }
}

library ECDSA {
    
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        
        if (signature.length != 65) {
            revert("signature's length is invalid");
        }

        
        bytes32 r;
        bytes32 s;
        uint8 v;

        
        
        
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := byte(0, mload(add(signature, 0x60)))
        }

        
        
        
        
        
        
        
        
        
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            revert("signature's s is in the wrong range");
        }

        if (v != 27 && v != 28) {
            revert("signature's v is in the wrong range");
        }

        
        return ecrecover(hash, v, r, s);
    }

    
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
        
        
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
    }
}

contract CompoundAdapter is CanReclaimTokens {
    using SafeERC20 for ERC20;
    ILiquidityPool liquidityPool;
    IRebalancer rebalancer;

    CEther cEther;
    mapping (address=>CErc20) cTokens;

    uint256 loansNonce;
    mapping (bytes32=>bool) loans;

    event LogLiquidate(address indexed borrower, address indexed collateralToken, address indexed debtToken, uint256 debtAmount);

    function () external payable {
    }

    constructor(ILiquidityPool _liquidityPool, IRebalancer _rebalancer) public {
        liquidityPool = _liquidityPool;
        rebalancer = _rebalancer;
    }

    function updateLiquidityPool(ILiquidityPool _newLiquidityPool) external onlyOwner {
        liquidityPool = _newLiquidityPool;
    }

    function updateRebalancer(IRebalancer _newRebalancer) external onlyOwner {
        rebalancer = _newRebalancer;
    }

    function register(address _underlying, address _cToken) external onlyOwner {
        require(_underlying != address(0x0), "Underlying asset cannot be 0x0");
        if (liquidityPool.isEther(_underlying)) {
            cEther = CEther(uint256(_cToken));
        } else {
            cTokens[_underlying] = CErc20(_cToken);
        }
    }

    function liquidate(address _borrower, CToken _collateralToken, address _debtToken, uint256 _debtAmount) external {
        _liquidate(_borrower, _collateralToken, _debtToken, _debtAmount);
        emit LogLiquidate(_borrower, address(_collateralToken), _debtToken, _debtAmount);
        loans[keccak256(abi.encodePacked(_borrower, address(_collateralToken), _debtToken, _debtAmount, loansNonce))] = true;
        loansNonce++;
    }

    function rebalance(address _borrower, CToken _collateralToken, address _debtToken, uint256 _debtAmount, uint256 _loansNonce) internal {
        bytes32 loanId = keccak256(abi.encodePacked(_borrower, address(_collateralToken), _debtToken, _debtAmount, _loansNonce));
        require(loans[loanId], "Loan does not exist");
        delete(loans[loanId]);
        uint256 cAmount = _collateralToken.balanceOf(address(this));
        _collateralToken.approve(address(rebalancer), cAmount);
        rebalancer.giveUnbalancedPosition(_debtToken, _debtAmount, address(_collateralToken), cAmount);
    }

    function _liquidate(address _borrower, CToken cToken, address _debtToken, uint256 _debtAmount) internal {
        liquidityPool.take(_debtToken, _debtAmount);
        if (liquidityPool.isEther(_debtToken)) {
           cEther.liquidateBorrow.value(_debtAmount)(_borrower, cToken);
        } else {
            CErc20 cerc20 = cTokens[_debtToken];
            ERC20(_debtToken).safeApprove(address(cerc20), _debtAmount);
            require(cerc20.liquidateBorrow(_borrower, _debtAmount, cToken) == 0, "liquidation failed");
        }
    }
}