Swapping Two Numbers Using Third Variable

program:

#include<stdio.h>
int main()
{
	int a,b,c;
	printf("enter First Num: ");
	scanf("%d",&a);
	printf("enter Second Num: ");
	scanf("%d",&b);
	printf("Before swapping a=%d and b=%d\n",a,b);
	c=a+b;
	a=c-a;
	b=c-b;
printf("After swapping a=%d and b=%d\n",a,b);
}

output: