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Loopy.sol

pragma solidity ^0.5.0;

contract Loopy {
    
    // 7750 gas
    // 5732 gas (optimized)
    function loop_1() public pure returns (uint acum) {
        for(uint i = 0; i < 100; i++) {
            acum++;
        }
    }
    
    // 6728 gas
    // 5710 gas (optimized)
    function loop_2() public pure returns (uint acum) {
        for(uint i = 0; i < 100; ++i) {
            ++acum;
        }
    }
}