Swapping two number without 3rd variable

C Program to Swapping two number without 3rd variable

#include<conio.h>
#include<stdio.h>
void main()
{
    int num1,num2;
    clrscr();
    printf("Enter first number : ");
    scanf("%d",&num1);
    printf("Enter second number : ");
    scanf("%d",&num2);
    printf("\n\nValue of A: %d   and  Value of B: %d",num1,num2);
    num1=num2+num1;
    num2=num1-num2;
    num1=num1-num2;
    printf("\n\n\n After swaping \n\n");
    printf("Value of A: %d   and  Value of B: %d",num1,num2);
    getch();
}


out put: