/* This program illustrates call be reference. The Swap function takes
   2 references to integers as parameters and swaps their values. Since
   they are references to variables in main, the corresponding variables
   in main are also changed. */

#include <iostream.h>

void Swap(int &, int &);  /* Swap takes 2 integer references as parameters */

main() {

   int a, b, c;
   a = 3; b = 7; c = 13;

   Swap(a, b);  /* this will set a to 7 and b to 3 */

   cout << a << " " << b << "\n"; /* should print 7 3 */

   Swap(b, c);  /* this will set b to 13 and c to 3 */

   cout << b << " " << c << "\n"; /* should print 13 3 */

   }


/* x and y are references to the corresponding variables in the call. Since
   they are refernces, changing x and y changes those corresponding
   variables. */

void Swap(int & x, int & y) {

   int temp;  /* temporary storage to help with swap */

   temp = x;  /* store x in temp for now */

   x = y;  /* move y into x */

   y = temp;  /* move stored value of x into y */

  return;

  }