Deploying to a Testnet

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract BasicMath {
function adder(uint _a, uint _b) external pure returns (uint sum, bool error) {
unchecked {
uint result = _a + _b;
if (result >= _a && result >= _b) {
return (result, false);
} else {
return (0, true);
}
}
}

function subtractor(uint _a, uint _b) external pure returns (uint difference, bool error) {
unchecked {
if (_b <= _a) {
return (_a - _b, false);
} else {
return (0, true);
}
}
}
}