Java Swap Two Numbers Without Using Third Variable

Program to swap two numbers without using third or temp variable.

/**
 * This program is used to swap two numbers without using third variable.
 * @author W3schools360
 */
public class SwapNumbers {
      /**
       * This method is used to swap no.s without using third variable.
       * @param num1
       * @param num2
       */
      static void swapNumbers(int num1, int num2){
            num1 = num1 + num2;
            num2 = num1 - num2;
            num1 = num1 - num2;

            System.out.println("After swapping: "+ num1 + " and " + num2);
      }     

      public static void main(String args[]){
            int num1 = 20;
            int num2 = 30;
           System.out.println("Before swapping:"+ num1 + " and " + num2);
            //method call
            swapNumbers(num1, num2);
      }

}

Output:

Before swapping no.s are : 20 and 30
After swapping no.s are : 30 and 20