pragma solidity >=0.7.0 <=0.7.4;
contract Calculator {
    int24 a = 0;
    int24 b = 0;
    int24[5] me;
    function addToArray(int24 val) public{
        me[0] = me[1];
        me[1] = me[2];
        me[2] = me[3];
        me[3] = me[4];
        me[4] = val;
    }
    function getLastResult() public view returns (int24[5] memory) {
        return me;
    }
    function setValues(int24 val1, int24 val2) public {
        a = val1;
        b = val2;
    }
    function getValues() public view returns(int24, int24) {
        return (a, b);
    }
    function getSum() public returns(int24) {
        int24 otv = a + b;
        addToArray(otv);
        return (otv);
    }
    function getDiff() public returns(int24) {
        int24 otv = a - b;
        addToArray(otv);
        return (a - b);
    }
    function getMul() public returns(int24) {
        int24 otv = a * b;
        addToArray(otv);
        return (a * b);
    }
    function getDiv() public payable returns(int24) {
        if(b == 0) { require(b != 0, "The second value must not be 0 "); }
        int24 otv = a / b;
        addToArray(otv);
        return(a / b);
    }
}