Jumping Numbers Java

PROGRAM TO PRINT ALL JUMPING NUMBERS SMALLER THAN OR EQUAL TO A GIVEN VALUE

import java.util.*;

import java.lang.*;

import java.io.*;

  

class MAIN {

  

    // Prints all jumping numbers smaller than or equal to x starting

    // with 'num'. It mainly does BFS starting from 'num'.

    public void bfs(int x, int num)

    {

        // Create a queue and enqueue 'i' to it

        Queue<Integer> q = new LinkedList<Integer>();

        q.add(num);

  

        // Do BFS starting from i

        while (!q.isEmpty()) {

            num = q.peek();

            q.poll();

            if (num <= x) {

                System.out.print(num + " ");

                int last_digit = num % 10;

  

                // If last digit is 0, append next digit only

                if (last_digit == 0) {

                    q.add((num * 10) + (last_digit + 1));

                }

  

                // If last digit is 9, append previous digit only

                else if (last_digit == 9) {

                    q.add((num * 10) + (last_digit - 1));

                }

  

                // If last digit is neighter 0 nor 9, append both

                // previous and next digits

                else {

                    q.add((num * 10) + (last_digit - 1));

                    q.add((num * 10) + (last_digit + 1));

                }

            }

        }

    }

  

    // Prints all jumping numbers smaller than or equal to

    // a positive number x

    public void printJumping(int x)

    {

        System.out.print("0 ");

  

        for (int i = 1; i <= 9 && i <= x; i++) {

            this.bfs(x, i);

        }

    }

  

    // Driver program

    public static void main(String[] args) throws IOException

    {

        int x = 40;

        GFG obj = new GFG();

        obj.printJumping(x);

    }

}

OUTPUT

0 1 10 12 2 21 23 3 32 34 4 5 6 7 8 9 

CREDITS: https://www.geeksforgeeks.org/print-all-jumping-numbers-smaller-than-or-equal-to-a-given-value/