/**********************************************************
* A Generic Linked List class with a private static inner Node class.
*********************************************************/
// We want to "throw" Java exceptions in our code,
// so we must import them first:

import java.util.NoSuchElementException;

public class GenericLinkedList<T> 
{
   /*******************************************************
     The private inner class "Node" 
    *******************************************************/
   // make Node class name of generic type
   private class Node<T>
   {
      // Node instance variable is generic
      private T item;
      private Node<T> next;

      // parameters in constructor generic
      public Node(T item, Node<T> next)
      {
         this.item = item;
         this.next = next;
      }

      public String toString(){ return "" + this.item; }
   } // End of private inner class "Node"


   /*****************************************************************/

   private Node<T> first;

   // Constructs an empty list
   public GenericLinkedList()
   {
      first = null;
   }

   // Returns true if the list is empty
   public boolean isEmpty()
   {
      return first==null;
   }

   // Returns a string representation
   public String toString()
   {
      String output = "";

      if(first == null) 
         return "[NULL]";

      Node<T> tmp = first;
      while(tmp != null) 
      {
         output += tmp + " -> ";
         tmp = tmp.next;
      }
      output += "[NULL]";
      return output;
   }

   // Inserts a new node at the beginning of this list
   // take in generic item; Nodes are generic
   public void addFirst(T item)
   {
      Node<T> newNode = new Node<T>(item, first);
      first = newNode;
   }



   /* ****************************************************************/
   // Assignment part 1: write the addAt(item, pos) method
   //
   //    addAt(item, pos) inserts item at position pos in the list
   //
   // Examples:
   //    addAt(item, 0)   will insert item as the new first node
   //    addAt(item, 1)   will insert item after the first node
   //
   // Throw NoSuchElementException if pos is pass the last node
   /* ****************************************************************/
   public void addAt(T item, int pos)
   {

   }



   /* ****************************************************************/
   // Assignment part 2: Write the removeAt(pos) method
   //
   //    removeAt(pos) Removes the node at position "pos" in the list
   //                  The item in the removed node is returned
   //
   // Examples:
   //    removeAt(0)   will remove the first node in list
   //    removeAt(1)   will remove the 2nd node in list
   //
   // Throw NoSuchElementException if pos is pass the last node
   /* ****************************************************************/
   public T removeAt(int pos)
   {
      return null;   // added so the program will compile...
   }


} // End of class