Call By Reference in C

/* Program for interchanging two numbers demonstrating Call By Reference in C */

#include<stdio.h>

#include<conio.h>

void swap(int *,int *);

void main()

{

            int x,y;

            x=15;y=20;

            clrscr();

            printf("x=%d, y=%d\n",x,y);

            swap(&x,&y);

            //printf("\n%x %x",&x,&y);

            printf("\nAfter interchanging: x=%d, y=%d\n",x,y);

            getch();

}

void swap(int *u,int *v)

{

            int temp;

            temp=*u;

            *u=*v;

            *v=temp;

            return;

}

Output: