public class LinkedList
{

	private Node head;
	private int listCount;

	public LinkedList()
	{
		
		head = new Node(null);
		listCount = 0;
	}

	public void add(Object data)
	
	{
		Node temp = new Node(data);
		Node current = head;
		
		while(current.getNext() != null)		{
			current = current.getNext();
		}
		
		current.setNext(temp);
		listCount++;
	}

	public boolean add(Object data, int index)
	
	{
		if (index<0 || index > listCount)
			return false;
		Node temp = new Node(data);
		Node current = head;
		
		for(int i = 1; i < index && current.getNext() != null; i++)
		{
			current = current.getNext();
		}
		
		temp.setNext(current.getNext());
		
		current.setNext(temp);
		listCount++;// increment the number of elements variable
		return true;
	}

	public Object get(int index)

	{
		// index must be 1 or higher
		if(index <= 0 || index > listCount)
			return null;

		Node current = head.getNext();
		for(int i = 1; i < index; i++)
		{
			if(current.getNext() == null)
				return null;

			current = current.getNext();
		}
		return current.getData();
	}

	public boolean remove(int index)

	{
		// if the index is out of range, exit
		if(index < 1 || index > size())
			return false;

		Node current = head;
		for(int i = 1; i < index; i++)
		{
			if(current.getNext() == null)
				return false;

			current = current.getNext();
		}
		current.setNext(current.getNext().getNext());
		listCount--; // decrement the number of elements variable
		return true;
	}

	public boolean remove(Object data)
	
	{

		Node current = head;

		while (current.getNext()!=null)
		{
			if (((current.getNext()).getData()).equals(data))
			{
				current.setNext(current.getNext().getNext());
				listCount--; // decrement the number of elements variable
				return true;
			}
			current = current.getNext();
		}

			return false;
	}
	public int size()

	{
		return listCount;
	}
	public String toString()
	{
		Node current = head.getNext();
		String output = "";
		while(current != null)
		{
			output += "[" + current.getData().toString() + "]";
			current = current.getNext();
		}
		return output;
	}
}