Java Program to Swap Two Numbers.

In this article, we will understand how to swap two numbers in Java. This is done using a temporary variable.

Below is a demonstration of the same −

Input

Suppose our input is −

value_1 : 45
value_2 : 70

Output

The desired output would be −

value_1 : 70
value_2 : 45

Algorithm

Step 1- Start
Step 2- Declare three integers: value_1, value_2 and temp
Step 3- Read the values
Step 4- Assign value_1 to temporary variable
Step 5- Assign value_2 to value_1
Step 6- Assign temporary variable to value_2
Step 6- Display the two values
Step 7- Stop

Example 1

Here, the input is being entered by the user based on a prompt. You can try this example live in ourcoding ground tool .

import java.util.Scanner;
public class NumbersSwap{
   public static void main(String[] args){
      int value_1, value_2, my_temp;
      System.out.println("The required packages have been imported");
      Scanner my_scan = new Scanner(System.in);
      System.out.println("A scanner object has been defined ");
      System.out.println("Enter the first number");
      value_1 = my_scan.nextInt();
      System.out.println("Enter the second number");
      value_2 = my_scan.nextInt();
      System.out.println("----Before swap----");
      System.out.println("The first value is " + value_1 + " and the second value is " + value_2 );
      my_temp = value_1;
      value_1 = value_2;
      value_2 = my_temp;
      System.out.println("----After swap----");
      System.out.println("The first value is " + value_1 + " and the second value is " + value_2 );
   }
}

Output

The required packages have been imported
A scanner object has been defined
Enter the first number
112
Enter the second number
34
----Before swap----
The first value is 112 and the second value is 34
----After swap----
The first value is 34 and the second value is 112

Example 2

public class NumbersSwap{
   public static void main(String[] args){
      int value_1 , value_2, my_temp;
      System.out.println("The required packages have been imported");
      value_1 = 45;
      value_2 = 70;
      System.out.println("----Before swap----");
      System.out.println("The first number is " + value_1 + " and the second number is " + value_2 );
      my_temp = value_1;
      value_1 = value_2;
      value_2 = my_temp;
      System.out.println("----After swap----");
      System.out.println("The first number is " + value_1 + " and the second number is " + value_2 );
   }
}

Output

The required packages have been imported
----Before swap----
The first number is 45 and the second number is 70
----After swap----
The first number is 70 and the second number is 45