Linked List

using System;

class MainClass {
    static void Main() {
        Console.WriteLine("Hello World!");
        LinkedList lst = new LinkedList(10);
        lst.Append(20);
        lst.PreAppend(40);
        lst.insert(2,55);
        lst.ReverseLinkedList();
    }
}

public class Node
{
    internal int data;  
    internal Node next;  
    public Node(int value)
    {
        this.data = value;
        this.next = null;
    }
}

public class LinkedList
{
    internal Node head;  
    internal Node tail;  
    internal int length;

    public LinkedList(int value)
    {
        Node newNode = new Node(value);
        newNode.next = head;
        this.head = newNode;
        this.length = 1;
        this.tail = this.head;
    }
    
    public void Append( int value)
    {
        
      Node newNode = new Node(value);
      this.tail.next = newNode;
      this.tail = newNode;
      this.length++;
    }
    
     public void PreAppend( int value)
    {
        
      Node newNode = new Node(value);
      newNode.next = this.head;
      this.head = newNode;
      this.length++;
    }
    
    public void insert(int index, int value)
    {
        int startindex = 0;
        if (this.length == 0)
        {
            return;
        }
        else if(index == 0)
        {
            PreAppend(value);
            return;
        }
        Node curnode = this.head;
        while(curnode.next !=null)
        {
            
            if((index-1) == startindex)
            {
                Node newnode = new Node(value);
                Node tempnode = curnode.next;
                curnode.next = newnode;
                newnode.next = tempnode;
                this.length++;
                return;
            }
            curnode = curnode.next;
            startindex ++;
        }
    
    }
    
    public void remove(int index)
    {
        Node curnode = this.head;
        int startindex = 0;
        Node prevnode = null;
        while(curnode.next !=null)
        {
            if(index == startindex)
            {
                prevnode.next = curnode.next;
                this.length--;
                return;
            }
            prevnode = curnode;
            curnode = curnode.next;
            startindex ++;
        }
    }
    
    public void ReverseLinkedList()
    {
        Node startNode = this.head;
        LinkedList reverselist = null;
        while(startNode.next != null)
        {
            if (reverselist == null)
            {
                reverselist = new LinkedList(startNode.data);
            }
            else
            {
                reverselist.PreAppend(startNode.data);
            }
           startNode = startNode.next;
        }
        
        reverselist.PreAppend(startNode.data);
        Node curnode = reverselist.head;
        while(curnode.next != null)
        {
           Console.WriteLine(curnode.data);
           curnode = curnode.next;
        }
        Console.WriteLine(curnode.data);
    }
    
    
}