#include <iostream>
using namespace std ;

void swap (int& x, int& y) {
   int temp ;

   temp = x ;
   x = y;
   y = temp ;
}

int main() {
   int a = 3, b = 5 ;

   cout << "a = " << a << ", b = " << b << endl ;
   swap(a,b) ;
   cout << "a = " << a << ", b = " << b << endl ;
}