library Math {
  /**
   * @dev Returns the largest of two numbers.
   */
  function max(uint256 a, uint256 b) internal pure returns (uint256) {
    return a >= b ? a : b;
  }

  /**
   * @dev Returns the smallest of two numbers.
   */
  function min(uint256 a, uint256 b) internal pure returns (uint256) {
    return a < b ? a : b;
  }

  /**
   * @dev Returns the average of two numbers. The result is rounded towards
   * zero.
   */
  function average(uint256 a, uint256 b) internal pure returns (uint256) {
    // (a + b) / 2 can overflow, so we distribute
    return (a / 2) + (b / 2) + (((a % 2) + (b % 2)) / 2);
  }
}
/**
 * @dev Standard math utilities missing in the Solidity language.
 */
function min(uint256 a, uint256 b) internal pure returns (uint256) {
    return a < b ? a : b;
  }
/**
 * @dev Returns the smallest of two numbers.
 */