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contracts...MusketeersGasProblem.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.10;

// gas golf
contract MusketeerGas {
    // The munitions manager of the Musketeer corps of Bannon Cocq has a limited amount of gunpowder (GAS) for their murder
    // They need to use what that have wisely.
    // In preparing the murder of X, they plan how much gunpowder to use.  Their stock is limited and their 
    // boss Bannon Cocq will be upset with them if they use too much.

    // how much is used in this contract as is?
    // 



    // start - 50908 gas
    // use calldata - 49163 gas
    // load state variables to memory - 48952 gas
    // short circuit - 48634 gas
    // loop increments - 48244 gas
    // cache array length - 48209 gas
    // load array elements to memory - 48047 gas

    uint public total;

    // start - not gas optimized
    // function sumIfEvenAndLessThan99(uint[] memory nums) external {
    //     for (uint i = 0; i < nums.length; i += 1) {
    //         bool isEven = nums[i] % 2 == 0;
    //         bool isLessThan99 = nums[i] < 99;
    //         if (isEven && isLessThan99) {
    //             total += nums[i];
    //         }
    //     }
    // }

    // gas optimized
    // [1, 2, 3, 4, 5, 100]
    function sumIfEvenAndLessThan99(uint[] calldata nums) external {
        uint _total = total;
        uint len = nums.length;

        for (uint i = 0; i < len; ++i) {
            uint num = nums[i];
            if (num % 2 == 0 && num < 99) {
                _total += num;
            }
        }

        total = _total;
    }
}