where am i done mistake?

Question about the task

Longest sequence

Java Syntax, Level 8, Lesson 6

Under discussion

please comment me a solution!!

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; /* Longest sequence */ public class Solution { public static void main(String[] args) throws IOException { ArrayList<Integer> list = new ArrayList<Integer>(); ArrayList<Integer> list1 = new ArrayList<Integer>(); BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); for(int i=0;i<10;i++){ list.add(Integer.parseInt(reader.readLine())); } int max=1; int search = list.get(0); for(int i=1;i<list.size();i++){ if(search == list.get(i)){ max++; } else{ list1.add(max); max = 1; search = list.get(i); } } int longest = list1.get(0); for(int i=1;i<list1.size();i++){ if(longest < list1.get(i)){ longest = list1.get(i); } } System.out.println(longest); } }

Comments (7)

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Bikash Daga

Level 0 , India

21 September 2021, 14:35

Try this Code -

import java.io.*;
public class IB {

   public static void main(String args[]) {
      String a = "100";
      String b = "100";
      if(a.equals(b))
      {
        System.out.println("Equal variables:");
        System.out.println(a.hashCode() + "\n" + b.hashCode());
      }

      String c = "100";
      String d = "500";

      if(!c.equals(d))
      {
          System.out.println("\nUn-equal variables:");
          System.out.println(c.hashCode() + "\n" + d.hashCode());
      }
      String Str = new String("We are learning hashCode in Java");
      System.out.println("Hashcode for Str :" + Str.hashCode() );
   }

}

Read this article for more information.

Sela

Level 20 , Poland

29 June 2020, 04:52

Learner has right. your code adds max value to the second list only if next number is different (lines 25), but loses it if an iteration in the Array is at the end. just shorten for tests the length of first array to let's say 4 numbers and run you code like 0 1 1 1. the result is 1. it is because the loop ends and you do nothing then with max value.

Kavita Rao

Level 13 , Rockville, United States

3 October 2019, 19:48

I also used the equals method instead of == when comparing. There is one scenario where the code does not work: if all the 10 numbers are identical, then the else code is not be executed and the list1 arraylist will be empty. Hence, get the out of bounds exception when trying to print out the max. Add another statement to add max list1 after exit the loop.

Ivan Robert Vecerina

Level 8 , Warrington, United Kingdom

25 August 2019, 13:00

the issue is that the "==" makes only a shallow comparison that doesn't work for any value over 127. try to use the "x.equals(y)" method instead. More Information here

shovan

Level 22 , Kolkata, india

28 December 2018, 04:43

put this: for(int i=1;i<list.size();i++) { if(search == list.get(i)) { max++; } else { max = 1; } search = list.get(i); list1.add(max); } it will work.

Arjun Kiruthivasan

Level 14 , Chennai, India

20 September 2018, 07:09

I TRIED BUT NOT WORK

Learner

Level 16 , India

20 September 2018, 04:35

Test your code with any other example like: 2, 4, 4, 4, 8, 8, 12, 12, 12, 12