//Use the below skeleton program.

#include <iostream>
using namespace std ;

int main ()
{
       int x1 = 100 ;
       int y1 = 200 ;
       int temp ;
       //TO DO exchange the values of x1 and y1
       //temp = x1 ;
       //x1 = y1 ;
       //y1 = temp ;
       x1 = x1 + y1 ;
       y1 = x1 - y1 ;
       x1 = x1 - y1 ;

       cout << "x1:" << x1 << " y1:" << y1 << endl ;
      return 0 ;
}