Last numbers are creating problem

Question about the task

Under discussion

Please some one explain clearly

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 { Scanner sc = new Scanner(System.in); ArrayList<Integer> list = new ArrayList<>(); for (int i = 0; i < 10; i++) { list.add(sc.nextInt()); } int count = 1; ArrayList<Integer> MaxCount = new ArrayList<>(); for (int j = 0; j < list.size(); j++) { if (j != list.size() - 1) { if (list.get(j) == list.get(j + 1)) { count++; } else if (list.get(j) != list.get(j + 1)) { MaxCount.add(count); count = 1; } } else { break; } } Collections.sort(MaxCount); System.out.println(MaxCount.get(MaxCount.size() - 1)); } }

Comments (1)

Popular
New
Old

You must be signed in to leave a comment

Guadalupe Gagnon

Level 37 , Tampa, United States

25 February 2019, 18:08

It is because your last loop cycle will break and the current count (which could potentially be the actual maximum) never gets added to your MaxCount list. To see this, modify your for loop like this (you can copy/paste):

for (int j = 0; j < list.size(); j++)
{
   if (j != list.size()-1) {
      System.out.print("Loop cycle: "+ (j + 1) +" - checking value: " + list.get(j));
      if (list.get(j) == list.get(j + 1)) {
         System.out.println(" - Match!, increasing count to " + (count+1));
         count++;
      } else if (list.get(j) != list.get(j + 1)) {
         System.out.println(" - No match. Adding " + count + " to MaxCount. Count now " + 1);
         MaxCount.add(count);
         count = 1;
      }
   }
   else
   {
      System.out.println("Break reached!");
      break;
   }
}

You can test with any numbers, but add in these: 2, 4, 4, 4, 8, 8, 14, 14, 14, 14 which has the longest sequence being the last 4. The output will show each loop cycle what is being done. Counts 1, 3, and 2 get added to the MaxCount list, but the break is reached before the count of 4 is added. Modify your code to add the current count before the break at line 39.