#include <iostream>
using namespace std;

void add(int x, int y)
{
    int r = x + y;
    cout << r << endl;
}

void sub(int x, int y)
{
    int r = x - y;
    cout << r << endl;
}

void mul(int x, int y)
{
    int r = x * y;
    cout << r << endl;
}