using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Node root = GetNodes();

                root = DeleteHeadOfADoublyLinkedList(root);

            TravarseNode(root);

            Node lastNode = GetLastNode(root);

            TravarseNodePrevious(lastNode);

    }

    public static Node GetNodes()

    {

        Node root = new Node();

             root.Data = 0;

             root.Next = null;

             root.Prev = null;

        Node lastNode = root;

         for(var i=1; i < 10; i++)

         {

             Node newNode = new Node();

                  newNode.Data = i;

             newNode.Prev = lastNode;

             lastNode.Next = newNode;

             lastNode = newNode;

         }

        return root;

    }

    public static void TravarseNode(Node root)

    {

         while(root != null)

         {

            Console.Write(root.Data + " ");

             root = root.Next;

         }

        Console.WriteLine();

    }

    public static void  TravarseNodePrevious(Node lastNode)

    {

        while(lastNode != null)

        {

            Console.Write(lastNode.Data + " ");

            lastNode = lastNode.Prev;

        }

        Console.WriteLine();

    }

    public static Node GetLastNode(Node root)

    {

        Node lastNode = null;

        while(root != null)

        {

            lastNode = root;

            root = root.Next;

        }

        return lastNode;

    }

    public static Node DeleteHeadOfADoublyLinkedList(Node root)

    {

        if(root==null) return root;

        Node newRootNode = root.Next;

             newRootNode.Prev = null;

        return newRootNode;     

    }

}

​

public class Node

{

    public int Data { get; set; }

    public Node Next { get; set; }

    public Node Prev { get; set; }

}

​

​

​