Java - Program to Swap Two Numbers Using Bitwise Operator

An intriguing method for exchanging two numbers in Java that does away with the requirement for a temporary variable is to use the bitwise operator. The XOR (^) bitwise operator is used in this method to swap the values. This is how it operates:

The Bitwise XOR Operator Explained

When two bits are compared, the XOR operator gives 1 if the bits are different and 0 otherwise.

For example:

0 ^ 0 = 0

0 ^ 1 = 1

1 ^ 0 = 1

1 ^ 1 = 0

Using this property, we can swap two numbers without using an additional variable.

Steps to Swap Two Numbers Using Bitwise XOR

Step 1: a = a ^ b - This stores the XOR of a and b in a.

Step 2: b = a ^ b - This retrieves the original value of a and stores it in b.

Step 3: a = a ^ b - This retrieves the original value of b and stores it in a.

Java Program to Swap Two Numbers Using Bitwise Operators

Here's a simple Java program that demonstrates this concept:

Program:

import java.util.Scanner;

public class SwapUsingBitwise {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        // Input: Read two numbers from the user

        System.out.print("Enter the first number (a): ");

        int a = scanner.nextInt();        

        System.out.print("Enter the second number (b): ");

        int b = scanner.nextInt();

        System.out.println("Before swapping: a = " + a + ", b = " + b);

        // Step 1: a = a ^ b

        a = a ^ b;        

        // Step 2: b = a ^ b (original value of a)

        b = a ^ b;      

        // Step 3: a = a ^ b (original value of b)

        a = a ^ b;

        // Output: Display the swapped values

        System.out.println("After swapping: a = " + a + ", b = " + b);       

        scanner.close();

    }

}