Swapping two numbers can be also known as exchanging the numbers between two variables. The swapping of two numbers without using a third variable or a temporary variable can be done by following the below simple steps:

For example, let’s take two numbers **x=20** (first variable) and **y=30** (second variable),

- Add both number (x+y) and store it in first variable (x). ie x = x + y
- Now Substract the second number from the first, and store it in y variable. ie. y = x – y
- Now to the step two again but store the value in x variable. ie. x = x – y

Let’s see the calculation steps:

x = x + y => x = 20 + 30 => 50

y = x – y => y = 50 – 20 => 30

x = x – y => x = 50 – 30 => 20

Let’s see the logic to do the same,

### Solution

*SwapTwoNumbers.java*

package com.javacodepoint.programs; public class SwapTwoNumbers { public static void main(String[] args) { //Initiating two integer numbers int x = 20, y=30; //Print both number before swapping System.out.println("x = "+x+", y= "+y); //Logic to swap these numbers without using a third variable x = x + y; y = x - y; x = x - y; //Printing the both number again after swapping System.out.println("x = "+x+", y= "+y); } }

**OUTPUT:**

x = 20, y= 30

x = 30, y= 20