My code not pass...

Question about the task

Longest string

Java Syntax, Level 7, Lesson 6

Archived

What's wrong here it seems just fine to me...?

1. Initialize the list of strings.
2. Read 5 strings from the keyboard and add them to this list.
3. Using a loop, find the longest string in the list.
4. Display the string. If there is more than one, display each on a new line.

Requirements:

In the main method, initialize the Solution class's existing strings field to a new ArrayList<>.
The program should read 5 strings from the keyboard and write them to the list of strings.
The program should display the longest string.
If several strings qualify as the longest, then you need to display each of them on a new line.

package com.codegym.task.task07.task0708; import java.io.BufferedReader; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.List; /* Longest string */ public class Solution { private static List<String> strings; public static void main(String[] args) throws Exception { //write your code here strings = new ArrayList<String>(); BufferedReader buffer = new BufferedReader(new InputStreamReader(System.in)); int max = strings.get(0).length(); String res = strings.get(0); for(int i=0;i<5;i++){ strings.set(i,buffer.readLine()); } for(int i=1;i<5;i++){ if(strings.get(i).length()>max) res = strings.get(i); else if(strings.get(i).length()==max){ res+="\n"+strings.get(i); } } System.out.println(res); } }

Comments (3)

Popular
New
Old

You must be signed in to leave a comment

Raivo Lapiņš

Level 18 , Riga, Latvia

21 May 2019, 06:17

solution

When I try to compile your program I get IndexOutOfBoundsException. I think it has to do with your logic here: You initialize a new ArrayList that will hold String objects with this line:

strings = new ArrayList<String>();

In the following 2 lines you try to access arraylist string element 0 and get the elements length and then you want to assign first element to String res.

int max = strings.get(0).length();
String res = strings.get(0);

Problem here is that strings arraylist has no elements so it throws OutOfBoundsException.

strings.set(i,buffer.readLine());

This line should use add() instead of set() method call. Set is used to insert element with new value at index i you specified, but add is used to append new element to the end of the list. Since your strings arraylist contains no elements at this point, your set method call will throw OutOfBoundsException again. I highly suggest that you download Intelij or any other IDEA and use Debug option to find mistakes in your code. It will make life a lot easier for you.

dean

Level 8 , Deutschland, Germany

21 May 2019, 06:28

lol i just asked someone else 2mins ago the exact question between .set & .add, and now i read your reply which made it all totally clear to me finally! :)) by the way i tried to use intelij-idea but the debugging doesn't work within the lessons code only if i debug my own code unrelated to the lessons-plugin... have you encountered this problem as well or is it just me? thanks again mate!

Raivo Lapiņš

Level 18 , Riga, Latvia

21 May 2019, 06:33

Debugging works well for me. You have to choose the line you want to start debugging from and then right click on the screen and press Debug.