pragma solidity ^0.4.21;

contract GlobalCalculator_V1 {
    uint[] internal _nums;

    function addNum(uint x) public {
        _nums.push(x);
    }

    function getSum() public view returns (uint sum) {
        for (uint i = 0; i < _nums.length; i++) {
            sum += _nums[i];
        }
    }
}