How to Swap two numbers if they are not same?

CODE

Swap two numbers if they are not same

int main()

{

    int a,b;

    printf("\n enter the value of a and b:");

    scanf("%d%d",&a,&b);

    if(a!=b)

    {

        a=a+b;

        b=a-b;

        a=a-b;

        printf("\n after swaping:\n a=%d,b=%d",a,b);

    }

    else

    {

        printf("\n numbers are same");

    }

}

Output:

enter the value of a and b:

2

4

 after swaping:

 a=4,b=2

AND

enter the value of a and b:

2

2

 numbers are same