Write a C Program to swap two numbers (integers) without using third variable

#include <stdio.h>

int main()

{

   int x, y;

   printf("Enter the value of x and y\n");

   scanf("%d%d", &x, &y);

   printf("Before Swapping\nx = %d\ny = %d\n",x,y);

   x    = x + y;

   x    = x - y;

   y    = x - y;

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

   return 0;

}