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Java program to enter a number and arrange its digits in descending order

By IncludeHelp Last updated : April 7, 2024

Problem statement

Write a Java program to enter a number and arrange its digits in descending order.

Example

Input Number: 76891
Output Number: 98761

Input a number and arrange its digits in descending order

To input a number, you can use the nextInt() method of the Scanner class and to arrange its digits in descending order, use a nested loop where the outer loop will run from 9 to 0 to compare each digit and the inner loop will construct the number from the digits.

Program to enter a number and arrange its digits in descending order in Java

import java.util.Scanner; // Import the Scanner class

public class Main {
  public static void main(String[] args) {
    // Create a Scanner object to input 
    Scanner myObj = new Scanner(System.in);
    
    System.out.println("Input an integer number: ");
    int number = myObj.nextInt(); // Read integer

    int result = 0; // To store sorted number
    
    // sorting the digits in reverese order
    for (int i = 9; i >= 0; i--) {
      int tempNum = number;
      while (tempNum > 0) {
        int digit = tempNum % 10;
        // Check for the largest digit in 
        // the given number
        if (digit == i) {
          result *= 10;
          result += digit;
        }
        tempNum /= 10;
      }
    }
    
    System.out.println("Input number is: " + number);
    System.out.println("Sorted number is: " + result);
  }
}

Output

The output of the above program is:

RUN 1:
Input an integer number: 
67891
Input number is: 67891
Sorted number is: 98761

RUN 2:
Input an integer number: 
123045
Input number is: 123045
Sorted number is: 543210