#include<stdio.h>
#include<conio.h>

void main()
{
    int x,y;
    x = 100;
    y = 200;
    clrscr();

    printf("Before Exchange : x = %d y = %d\n\n",x,y);
    exchange(&x,&y);
    printf(" After Exchange : x = %d y = %d\n\n",x,y);
    getch();
}
exchange(a,b)
int *a,*b;
{
    int t;
    t = *a;
    *a = *b;
    *b = t;
    return(*a,*b);
}