Is this bugged i cant verify

Question about the task

Replace recursion

Java Multithreading, Level 9, Lesson 9

Resolved

I have the same output and i did not change the main method but it still wont verify

Two integers, A and B, are randomly generated by the program. You need to display all integers from A to B inclusive, in ascending order, if A is less than B, or in descending order otherwise.

The task is implemented using recursion.
Sometimes the program throws an Exception (java.lang.StackOverflowError) on "main" thread.

Here's your task: rewrite the code so that it does not use recursion.
Rename the recursion() method to getAllNumbersBetween().

Requirements:

The recursion() method must be renamed to getAllNumbersBetween().
There should not be recursive calls in any method of the Solution class.
There must not be a space at the end of the output line with the sequence of numbers.
The behavior of the program should remain the same.
Don't change the main() method.

package com.codegym.task.task29.task2913; import java.util.Random; /* Replace recursion */ public class Solution { private static int numberA; private static int numberB; public static String getAllNumbersBetween(int a, int b) { String sb = ""; if (b > a) { for (int j = a; j <= b; j++) { int i = 1 * j + (a - 1); sb += j + " "; } } else if (a > b) { for (int j = a; j >= b; j--) { int i = -1 * b + (a - b + 1) * 2 + 1; sb += j + " "; } } else sb += a; return sb.trim(); } public static void main(String[] args) { Random random = new Random(); numberA = random.nextInt() % 1_000; numberB = random.nextInt() % 10_000; System.out.println(getAllNumbersBetween(numberA, numberB)); System.out.println(getAllNumbersBetween(numberB, numberA)); } }

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Roman

Level 41

16 October 2019, 07:39

solution

We'll fix it soon. Now, please, replace your main method

public static void main(String[] args) {
        Random random = new Random();
        numberA = random.nextInt(1000);
        numberB = random.nextInt(1000);
        System.out.println(getAllNumbersBetween(numberA, numberB));
        System.out.println(getAllNumbersBetween(numberB, numberA));
    }

Nicolas Huet

Level 41 , Provins, France

17 October 2019, 13:40

Thank you :)

Nicolas Huet

Level 41 , Provins, France

15 October 2019, 16:46

I have exactly the same issue...

public static String getAllNumbersBetween(int a, int b) {
        StringBuilder sb = new StringBuilder();
        if (a == b){
            return Integer.toString(a);
        }
        else if (a > b){
            for (int i = a; i >= b; i--){
                sb.append((i)).append(" ");
            }
        }
        else {
            for (int i = a; i <= b ; i++){
                sb.append(i).append(" ");
            }
        }
        return sb.toString().trim();
    }

It doesn't make any sense to me...

Guadalupe Gagnon

Level 37 , Tampa, United States

15 October 2019, 18:33

try copying your method (lines 14-29 for the OP), reset the task, paste your method over the recursion method. See if that clears the problem. Otherwise the task may be bugged. Also, a little modification that, to me, makes sense. I'm not saying this is "better" (and it does the same exact thing) but it's a little cleaner and doesn't add extra spaces that need to be trimmed:

public static String getAllNumbersBetween(int a, int b) {
   StringBuilder sb = new StringBuilder();
   sb.append(a); // add a
   /*if (a == b){
         return Integer.toString(a);
   }*/
   if (a > b)
      for (int i = a - 1; i >= b; i--)// change here
         sb.append(" " + i);
   else if (a < b)
      for (int i = a + 1; i <= b ; i++) // change here
                sb.append(" " + i);

   return sb.toString(); // no need to trim
}

Nicolas Huet

Level 41 , Provins, France

15 October 2019, 19:54

Hello, I tried to reset and past it and it didn't work... I even tried with your solution (which effectively cleaner!) and it didn't work either. I asked the staff, we'll see but it seems buggy for real this time^^

Guadalupe Gagnon

Level 37 , Tampa, United States

15 October 2019, 19:58

I have run into plenty of bugged tasks. If it is bugged, and I would think it is being that all this code works according to the requirements, Codegym will fix it next time they update the website. Skip it for now and come back to it later.

Nicolas Huet

Level 41 , Provins, France

15 October 2019, 20:48

Yep I did all the other tasks in this session and I'm moving forward indeed :) Thanks for taking the time to help!