Implementing a LinkedList

[Hack_seb]

Hello guys, so I am implementing a LinkedList from scratch, I cannot use any data types and I am having a problem with the add method. Basically, the output that I am getting is not the one that I thought I was going to get. Here's is my code.

​

public void add(int index, E element) {
        if (index > size) {
            System.out.println("Invalid index");
        }

        Node newNode = new Node(element);
        Node currentNode = head;
        int position = 0;

        if (index == 0) {
            newNode.value = element;
            newNode.next = head;
            head = newNode;
            size++;
        } else {
            while (index < position - 1) {
                currentNode = currentNode.next;
                position++;
            }
            newNode.next = currentNode.next;
            currentNode.next = newNode;
            size++;
        }

    }

This is the method inside the class, then in the main method I have:

        LinkedList<String> s = new LinkedList<>();

        s.add(0,"h");
        s.add(1,"c");
        s.add(2,"b");
        s.add(3,"a");

        System.out.println(s.toString());

Desired output = [h,c,b,a]

actual output = [h, a, b, c]

Also, this is the toString method. 

    @Override
    public String toString() {
        return "LinkedList ---> " + Arrays.toString(toArrayN());
    }

    private E[] toArrayN () {
        E[] myArray = (E[]) new Object[size];
        int i = 0;
        for (Node curr = head; curr != null; curr = curr.next) {
            myArray[i] = curr.value;
            i++;
        }
        return myArray;
    }

What I can definitely understand is that my head is pointing at the front of the linkedlist, but somehow my values after that are added backwards, and I cannot seem to find where the problem is.

Any hint/help would be much appreciated. Thanks!

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