Swapping two numbers without using a third variable

This is a program using which you can swap two numbers without using a third variable.
This program is crafted using Java Language.

import java.util.Scanner;
class swap
{
     public static void main (String []args)
     {
            Scanner s= new Scanner(System.in);
            System.out.print("Enter The Value Of A: ");
            int a=s.nextInt();
            System.out.print("Enter The Value Of B: ");
            int b=s.nextInt();
            a=a+b;
            b=a-b;
            a=a-b;
            System.out.println("Swapped, a: "+a+", b: "+b);
      }
}

Description:
This program swaps the two number without using a third value. Let say the value of a is 10 and b is 5.
First Calculation: a=a+b, So a=10+5=15.
Second Calculation: b=a-b, So b=15-5=10.
Third Calculation: a=a-b, So a=15-10=5.
Now the values of both a and b have successfully changed. Instead of add and sub, you can alternatively use mul and div.
The Complexity is of order 1, O(1).