Q. Add two no. without using third variable ?

THE OUTPUT WOULD BE

#include<stdio.h>
#include<conio.h>
  void main( )
  { clrscr( );
int a,b;
printf("Enter a:");
scanf("%d",&a);
printf("Enter b:");
scanf("%d",&b);
a=a+b;
printf("Sum=%d",a);
getch( );
  }