- How to reverse digits of a number using loop.
- Write a Java program to reverse the sequence of digits of a number.

To **reverse a number in Java**, we will first take an integer as input form user and store it in a int variable. We will **reverse the digits** of input number using below mentioned algorithm. After reversing we will prints the reversed number on screen. In this program, we will learn how to split a number into digits one by one and then **reverse the sequence of digits**.

**Algorithm to reverse digits of a number**

- Get the least significant digit(right most digit or last digit) of the number.

lastDigit = number%10; - Append it at the end of reverse number.

reverse = (reverse * 10) + lastDigit; - Remove right most digit from number.

number = number/10; - Repeat this process till number is greater than zero.

## Java program to reverse digits of a number

package com.tcc.java.programs; import java.io.*; public class ReverseNumberDigits { public static void main(String args[]) throws Exception { int num=0, reverse, lastDigit; System.out.println("Enter an Integer"); //take user input BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); num = Integer.parseInt(br.readLine()); reverse = 0; while(num != 0) { lastDigit = num%10; reverse = reverse*10 + lastDigit; num = num/10; } // Print output System.out.println("Reversed Number : " + reverse); } }Output

Enter an Integer 12345 Reversed Number : 54321