LAB 4

1. 

	public void add(E element) {
		if (numElements == 0) {
			head = new Node<E>(element);
			head.next = head;
		}
		else {
			Node<E> newNode = new Node<E>(element);
			newNode.next = head.next;
			head.next = newNode;
		}
		numElements++;
	}

2.

	public void display(int index) {
		if (index < 0) {
			System.out.println("Invalid index: negative value");
			return;
		}
		if (numElements == 0)
			return;
		Node<E> nodeRef = head;
		for (int i = 0; i < index % numElements; i++) 	// Advance to starting node
			nodeRef = nodeRef.next;
		Node<E> startingNode = nodeRef;
		do {
			System.out.print(nodeRef.data);
			nodeRef = nodeRef.next;
		} while (nodeRef != startingNode);
		System.out.println();		
	}