Data Structures -- Linked List - Find the nth last element in linked list.

hello..It's my first time here to visit..I want to ask for help in making a main class of my linked list in queue..Here's what is asking for:

  If the input satisfies partial ordering, then the algorithm will terminate when the
Queue is empty
– If a loop exists, it will also terminate but will not output the elements in the
Loop. Instead, it will just inform the user that a loop is present:

here's the code:

interface Queue{

    /* Insert an item */
    void enqueue(Object item) throws QueueException;

    /* Delete an item */
    Object dequeue() throws QueueException;
}


Class QueueException extends RuntimeException{
    public QueueException(String err){
        super(err);
    }
}

another file:

class LinkedQueue implements Queue{
    Node front, rear;

    /* Create an empty queue */
    LinkedQueue(){
    }

    /* Create a queue with node and initially */
    LinkedQueue(Node and){
        front = and;
        rear = and;
    }

    /* Inserts an item onto the queue */
    public void enqueue(Object item){
        Node and = new Node(item, null);
        if (front == null) {
            front = and;
            rear = and;
        }
        else{
            rear.Link = and;
            rear = and;
        }
    }

    /* Deletes an item from the queue */
    public Object dequeue() throws QueueException{
        Object x;
        if (front == null) throw new QueueException
                        ("Retrieving from an empty queue.");
            x = front.Info;
        front = front.Link;
        return x;
    }

    /* Main method to test the queue */
    public static void main(String args[]){
        LinkedQueue q = new LinkedQueue();
        for (int I=11; I>0; I--){
            q.Enqueue(new Integer(I));
            System.Out.Println(I +" inserted");
        }
        for (int I=12; I>0; I--)
            System.Out.Println(q.Dequeue() + " retrieved");
    }

}

thank you...God Bless 

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QUOTE(vivek.m @ Nov 24 2008, 08:27 PM)

the most basic and the only answer that came to my mind (actually, my frnd's mind. I am too laazy to use mine)  is to find length and then to find the (l-n)th element with o(n2) complexity.
i am interested in your answer.. it's more than a month since you posted your question. 

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QUOTE(varalu @ Oct 27 2007, 09:09 AM)

@sanjay0828
Good one... the expected solution.

Again... i want a simpler solution. What will be the basic answer that comes to your mind if i give this problem.??
Very basic.. ..

If no answer i will be posting it in my next post.

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