Program to show swap of two no's without using third variable.

			#include<stdio.h>
			#include<conio.h>
			void main()
			{
			int a,b;
			clrscr();
			printf("enter value for a & b: ");
			scanf("%d%d",&a,&b);
			a=a+b;
			b=a-b;
			a=a-b;
			printf("after swapping the value of a & b: %d %d",a,b);
			getch();
			}
Output:
enter value for a & b: 4 5
after swapping the value of a & b: 5 4