#include <iostream>

using namespace std;


void swap(int& a, int& b){
    int tmp;
    tmp = a;
    a = b;
    b = tmp;
}

int main()
{

    int a = 1, b = 2;
    swap(a, b);
    cout << "a = " << a << endl;
    cout << "b = " << b << endl;
    return 0;
}