Java Program to Reverse a Number - The Coding Shala

Home >> Java Programs >> Reverse a Number

 In this post, we will learn how to Reverse a Number in Java.

Java Program to Reverse a Number

Take a number as input and Write a Java Program to Reverse the given number.

Example 1:
Input: 213
Output: 312

Approach

Step 1: Take the last digit using the number % 10. the Modulo (%) operator returns the remainder.

Step 2: Append this last digit to reversed number. Reverse = Reverse * 10 + lastdigit

Step 3. Remove the last digit from the number using the number / 10.

Java Program: 

// Java program to Reverse a Number

import java.util.Scanner;

public class Main {
	
	public static void main(String[] args) { 
		
		Scanner sc = new Scanner(System.in);
		
		// take input 
		System.out.println("Enter a Number: ");
		int num = sc.nextInt();
		
		int reverseNum = 0;
		while(num > 0) {
			// take last digit;
			int digit = num % 10;
			
			// add it in reverse
			reverseNum = reverseNum * 10 + digit;
			
			// remove last digit from number
			num = num / 10;
		}
		
		System.out.println("Reversed Number is: " + reverseNum);
		
		sc.close();
	}
}

Output: 

Enter a Number: 
514
Reversed Number is: 415


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