Question

Java

In your own custom ArrayList<E> class(do not use Java Array List API) use Array algorithm

Write a static function called RemoveNullElements() without creating another array.

that remove Null elements and shift all the rest of the elements to the left/front (small indexes) of the array without changing the size or length of the original array( this meant the front of the array will have all the not Null elements, and the other haft will be empty/Null.

Please provide test code as well, thanks

Answer 1

import java.util.ArrayList;
import java.util.Arrays;

public class RemoveNullElementsTest {

    public static <E> void RemoveNullElements(ArrayList<E> list) {
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i) == null) {
                list.remove(i);
                i--;
            }
        }
    }

    public static void main(String[] args) {
        ArrayList<Integer> integers = new ArrayList<>(Arrays.asList(3, 9, null, 5, null, 7, 1, null));
        System.out.println("Original integers: " + integers);
        RemoveNullElements(integers);
        System.out.println("Modified integers: " + integers);
    }
}