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SafeMath.sol
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pragma solidity ^0.8.0;
library SafeMath {
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
}
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b > a) return (false, 0);
return (true, a - b);
}
}
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
}
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a / b);
}
}
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a % b);
}
}
function add(uint256 a, uint256 b) internal pure returns (uint256) {
return a + b;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return a - b;
}
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
return a * b;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return a / b;
}
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return a % b;
}
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b <= a, errorMessage);
return a - b;
}
}
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a / b;
}
}
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a % b;
}
}
}