// A C++ style CH applet executed across the network 
#include<stdio.h>
void swap(int &a, int &b); 
int main() {
  int x = 4;
  int y = 5;
  printf("x = %d, y = %d\n", x, y);
  swap(x,y); // pass by reference
  printf("x = %d, y = %d\n", x, y);
  getchar();
}
void swap(int &a, int &b) {
  int temp;
  temp = a;
  a = b;
  b = temp;
}