Why its fail

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capacity=capacity+(capacity+capacity/2); String[] temp = new String[capacity]; for (int j = 0; j < elements.length; j++) { temp[j] = elements[j]; } elements = temp;

ArrayList is a list that stores a dynamically expanding array of elements. We will now implement our own version of a list that stores strings. The CustomStringArrayList class has three fields:

String[] elements is an array for storing elements (ArrayList stores values in a similar array). Initially, its size is 10 (capacity = 10).
int size stores the number of elements currently stored in the list. Its initial value is 0.
int capacity is the current capacity of the elements array. It increases as data is added.

To simplify the implementation, we will have only two methods:

A public add(String) method that adds an element to the array. This method will help us track when the array needs to dynamically expand.
When the array is full (size == capacity), the grow() method is called to expand the array.
A private grow() method that sets the elements field equal to a new array with a capacity (capacity) that is one and a half times larger than that of the old array and copies the data from the old array to the new one in the same order. The capacity field should increase along with the size of the array.

Requirements:

The CustomStringArrayList class should have private non-static int size, int capacity, and String[] elements fields.
The CustomStringArrayList class should have a no-argument constructor that initializes the size field to 0, the capacity field to 10, and the elements field to a new array whose size is determined by the capacity variable.
The CustomStringArrayList class should have a public void add(String) method.
The CustomStringArrayList class should have a private void grow() method.
The grow() method must work in accordance with the task conditions.
Do not change the add(String) method.

package en.codegym.task.pro.task12.task1212; public class Solution { public static void main(String[] args) { CustomStringArrayList arrayList = new CustomStringArrayList(); for(int i = 0; i < 25; i++) { arrayList.add("count" + i); } //System.out.println(arrayList.capacity); } }

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Durairaj

Level 108 , Coimbatore,Tamil Nadu, India

Expert

12 October 2023, 11:01

private void grow() { int newCapacity = capacity + (capacity / 2); // Increase capacity by 50% String[] temp = new String[newCapacity]; for (int i = 0; i < size; i++) { temp[i] = elements[i]; } elements = temp; capacity = newCapacity; } ---------------------------------------------------------------------------------------------------------- @Shraddha Lambat Try Now may be working

Shraddha Lambat

Level 20 , Mumbai , India

Expert

7 October 2023, 01:36

capacity=(int)(capacity*2.5);
        String[] temp = new String[capacity];
        for (int j = 0; j < elements.length; j++) {
            temp[j] = elements[j];
        }
        elements = temp;

still not working

Thomas

Level 41 , Bayreuth, Germany

7 October 2023, 06:39

solution

Lupe said that you increased the capacity by a factor of 2.5 but the requirements ask for 1.5. Your fixed version still increases capacity by a factor of 2.5

Guadalupe Gagnon

Level 37 , Tampa, United States

6 October 2023, 18:33

solution

It looks like the grow() method is increasing the capacity of the array by 2.5 instead of 1.5. I would fix that.