Can't pass the last requirement

Question about the task

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Hey, I wonder what is wrong with my code. It gives the right result as far as I can tell, but I don't pass the last requirement. Anyone who can help me ?

1. Create a list of numbers.
2. Use the keyboard to add 10 numbers to the list.
3. Display the length of the longest sequence of repeating numbers in the list.

Example for the list 2, 4, 4, 4, 8, 8, 4, 12, 12, 14:
3

The value is 3, because the longest sequence of repeating numbers is three fours.

Requirements:

The program must display a number on the screen.
The program should read values from the keyboard.
In the main method, declare an ArrayList variable with Integer elements and immediately initialize it.
The program should add 10 numbers to the collection in accordance with the conditions.
The program should display the length of the longest sequence of repeating numbers in the list.

package com.codegym.task.task08.task0812; import java.io.*; import java.util.ArrayList; import java.util.Collections; import java.util.Scanner; /* Longest sequence */ public class Solution { public static void main(String[] args) throws IOException { ArrayList<Integer> list = new ArrayList<>(); Scanner sc = new Scanner(System.in); int highestSequenceNumber = 1; int sequenceNumber = 1; for (int i = 0; i < 10; i++) { list.add(sc.nextInt()); } Collections.sort(list); for (int i = 0; i < list.size()-1; i++) { if (!list.isEmpty()) { int head = list.get(i); int next = list.get(i+1); if (head == next) { sequenceNumber += 1; } if (head != next) { sequenceNumber = 1; } if (sequenceNumber > highestSequenceNumber) { highestSequenceNumber = sequenceNumber; } } } System.out.println(highestSequenceNumber); sc.close(); } }

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Anitamalina

Level 18 , København, Denmark

14 August 2021, 01:29

Okay, I solved it now ;) (Just by conversation with myself) lol. There is a bug below, for the sequence: right result: 4 2 2 4 4 4 4 8 8 12 14

Guadalupe Gagnon

Level 37 , Tampa, United States

14 August 2021, 02:34

This is called the rubber ducky method of debugging: wikipage

Anitamalina

Level 18 , København, Denmark

14 August 2021, 10:19

haha 😎🤓🦆

Anitamalina

Level 18 , København, Denmark

14 August 2021, 01:24

to everyone following this - it's the sequence NEXT to each other.. not the frequency of a number in a list (I just realised this). Sooo, I just changed my code, once again to be the next to, but I still fail..

public class Solution {
    public static void main(String[] args) throws IOException {
        ArrayList<Integer> list = new ArrayList<>();
        Scanner sc = new Scanner(System.in);

        int highestSequenceNumber = 1;
        int sequenceNumber = 1;

        for (int i = 0; i < 10; i++) {
            list.add(sc.nextInt());
        }

        for (int i = 0; i < list.size() -1; i++) {
            int head = list.get(i);
            int next = list.get(i+1);

                if (head == next) {
                    sequenceNumber += 1;
                }

                if (sequenceNumber > highestSequenceNumber) {
                    highestSequenceNumber = sequenceNumber;
                    sequenceNumber = 1;
                }
            }

        System.out.println(highestSequenceNumber);
        sc.close();
    }
}

Anitamalina

Level 18 , København, Denmark

14 August 2021, 00:53

useful

and now I changed my code to not have the sorting, but still don't pass the last requirement...

public class Solution {
    public static void main(String[] args) throws IOException {
        ArrayList<Integer> list = new ArrayList<>();
        Scanner sc = new Scanner(System.in);

        int highestSequenceNumber = 1;
        int sequenceNumber = 0;

        for (int i = 0; i < 10; i++) {
            list.add(sc.nextInt());
        }

        for (int i = 0; i < list.size()-1; i++) {
            sequenceNumber =0;

            for (int j = i; j < list.size()-1; j++) {
                int head = list.get(i);
                int next = list.get(j+1);

                if (head == next) {
                    sequenceNumber += 1;
                }

                if (sequenceNumber > highestSequenceNumber) {
                    highestSequenceNumber = sequenceNumber;
                }
            }

        }

        System.out.println(highestSequenceNumber);
        sc.close();
    }
}

Anitamalina

Level 18 , København, Denmark

14 August 2021, 00:32

oooh, okay. tested on other input! thank you! easy fix, but it still doesn't work, same issue... I fail in the last requirement.. maybe it is the sort, I just don't understand why I'm not allowed... ?

public class Solution {
    public static void main(String[] args) throws IOException {
        ArrayList<Integer> list = new ArrayList<>();
        Scanner sc = new Scanner(System.in);


        int highestSequenceNumber = 1;
        int sequenceNumber = 0;

        for (int i = 0; i < 10; i++) {
            list.add(sc.nextInt());
        }

        Collections.sort(list);

        for (int i = 0; i < list.size()-1; i++) {
            int head = list.get(i);
            int next = list.get(i+1);

            if (head == next) {
                sequenceNumber += 1;
            }

            if (head != next) {
                sequenceNumber = 0;
            }

            if (sequenceNumber > highestSequenceNumber) {
                highestSequenceNumber = sequenceNumber;
            }
        }

        System.out.println(highestSequenceNumber);
        sc.close();
    }
}

Lisa

Level 41

13 August 2021, 13:37

maybe if you do not sort the list? Look at the codegym example 2, 4, 4, 4, 8, 8, 4, 12, 12, 14. The result for the longest sequence is 3. Your code would result in 4. uuuhhh, ahhhh, that feels so good. I found a bug, a bug... isn't that crazy, crazy 🤪😜