Swap two number without using third variable in C

Program:

#include<stdio.h>

int main(){

int a,b,temp;

a=15;

b=8;

printf("Before Swapping\na=%d\nb=%d\n",a,b);

a = a + b;

    b = a - b;

    a = a - b;

printf("\n\tAfter Swapping\n\ta=%d\n\tb=%d\n",a,b);

 

 return 0;

}

Expected O/P:

Before Swapping

a=15

b=8

After Swapping

a=8

b=15