└── contracts
    └── BasicMath.sol


/contracts/BasicMath.sol:
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 1 | // SPDX-License-Identifier: MIT
 2 | pragma solidity ^0.8.7;
 3 | 
 4 | contract BasicMath {
 5 | 
 6 |     function adder(uint _a, uint _b) external pure returns (uint sum, bool error) {
 7 |         unchecked{
 8 |             sum = _a + _b;
 9 |             if(sum >= _a || sum >= _b){
10 |                 return (sum, false);
11 |             } else{
12 |                 return (0, true);
13 |             }
14 | 
15 |         }
16 |     }
17 | 
18 |     function subtractor(uint _a, uint _b) external pure returns (uint difference, bool error) {
19 |         unchecked{
20 |             difference = _a - _b;
21 |             if(difference <= _a){
22 |                 return (difference, false);
23 |             } else{
24 |                 return (0, true);
25 |             }
26 | 
27 |         }
28 |     }
29 | }


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