#include <iostream>

using namespace std;

int main ()
{
    bool done = false;

    do  {        //loops program

        begin_cycle:;
        int a, b;
        string opr;

        cout << "First Number: ";
        cin >> a;
        cout << "Second Number: ";
        cin >> b;
        begin_cycle2:;
        cout << "Operator?[a][s][m][d]: ";
        cin >> opr;

        if ( opr == "a" )
        {
            int r;
            r=a+b;
            cout << "Result: " << r << "\n";
            goto begin_cycle;
        }
        else if ( opr == "s" )
        {
            int r;
            r=a-b;
            cout << "Result: " << r << "\n";
            goto begin_cycle;
        }
        else if (opr == "m" )
        {
            int r;
            r=a*b;
            cout << "Result: " << r << "\n";
            goto begin_cycle;
        }
        else if ( opr == "d" )
        {
            int r;
            r=a/b;
            cout << "Result: " << r << "\n";
            goto begin_cycle;
        }
        else if ( opr == "stop" )
        {
            goto end_cycle;
        }
        else
        {
            cout << opr << "is not an operator." << endl;
            goto begin_cycle2;
        }
    } while (!done);
    end_cycle:;
}