Reversing a singly linked list iteratively

Question

Has to be O(n) and in-place (space complexity of 1). The code below does work, but is there a simpler or better way?

public void invert() {
    if (this.getH         


        

Answer 1

Using a self-contained implementation, i.e. the List is represented by the head Node:

public class Node
{
    Node next;
    E value;

    public Node(E value, Node next)
    {
        this.value = value;
        this.next = next;
    }

    public Node reverse()
    {
        Node head = null;
        Node current = this;
        while (current != null) {
            Node save = current;
            current = current.next;
            save.next = head;
            head = save;
        }
        return head;
    }
}