pragma solidity 0.4.20;


/**
 * @title SafeMathUint256
 * @dev Uint256 math operations with safety checks that throw on error
 */
library SafeMathUint256 {
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a * b;
        require(a == 0 || c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        // assert(b > 0); // Solidity automatically throws when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        return a - b;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);
        return c;
    }

    function min(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a <= b) {
            return a;
        } else {
            return b;
        }
    }

    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a >= b) {
            return a;
        } else {
            return b;
        }
    }

    function getUint256Min() internal pure returns (uint256) {
        return 0;
    }

    function getUint256Max() internal pure returns (uint256) {
        return 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
    }

    function isMultipleOf(uint256 a, uint256 b) internal pure returns (bool) {
        return a % b == 0;
    }

    // Float [fixed point] Operations
    function fxpMul(uint256 a, uint256 b, uint256 base) internal pure returns (uint256) {
        return div(mul(a, b), base);
    }

    function fxpDiv(uint256 a, uint256 b, uint256 base) internal pure returns (uint256) {
        return div(mul(a, base), b);
    }
}