import java.lang.*;

class LinkedList
{
  Node head;
  // not using parameterized constructor would by default
  // force head instance to become null
  // Node head = null;  // can also do this, but not required

  // Node Class
  class Node
  {
    int data;
    Node next;

      Node (int x)		// parameterized constructor
    {
      data = x;
      next = null;
    }
  }
  public Node insertStart (int data)
  {
    // Creating newNode memory & assigning data value
    Node newNode = new Node (data);
    // assigning this newNode's next as current head node
    newNode.next = head;

    // re-assigning head to this newNode
    head = newNode;

    return head;
  }

  public void insertLast (int data)
  {
    // Creating newNode memory & assigning data value
    Node newNode = new Node (data);

    // if Linked List was empty, entering first node
    if (head == null)
      {
	head = newNode;
	return;
      }

    // required to traverse the Linked List
    Node temp = head;

    // traverse till the last node in Linked List
    while (temp.next != null)
      temp = temp.next;

    // assigning the current last node's next to this newNode
    // thus newNode becomes the last node in Linked List
    temp.next = newNode;

  }

  public void insertPosition (int n, int data)
  {
    int size = calcSize (head);

    // Can only insert after 1st position
    // Can't insert if position to insert is greater than size of Linked List
    if (n < 1 || n > size)
      {
	System.out.println ("Can't insert\n");

      }
    else
      {
	Node newNode = new Node (data);
	// required to traverse
	Node temp = head;

	// traverse to the nth node
	while (--n > 0)
	  temp = temp.next;

	// assigning this newNode's next to nth node's next
	newNode.next = temp.next;
	// assigning the nth node's next to this newNode
	temp.next = newNode;
	// newNode added after nth node
      }
  }


  void printk (int k)
  {
    int length = 0;
    Node temp = head;

    for (int i = 0; temp != null; i++)
      {
	temp = temp.next;
	length++;
      }
    temp = head;

    //to get kth node from the end we can also say that we want (length-k+1) node from the beginning
    int i = 1;
    while (i < length - k + 1)
      {
	temp = temp.next;
	i++;
      }
    System.out.println (k + "th Node from the end is " + temp.data);
  }


  public void display ()
  {
    Node node = head;
    //as linked list will end when Node reaches Null
    while (node != null)
      {
	System.out.print (node.data + " ");
	node = node.next;
      }
    System.out.println ();
  }
  // required for insertPosition() method
  public int calcSize (Node node)
  {
    int size = 0;
    // traverse to the last node each time incrementing the size
    while (node != null)
      {
	node = node.next;
	size++;
      }
    return size;
  }
}

public class Main
{
  public static void main (String args[])
  {
    LinkedList ll = new LinkedList ();

      ll.insertStart (3);
      ll.insertStart (2);
      ll.insertStart (1);
      ll.insertLast (5);
      ll.insertLast (6);
      ll.insertLast (7);
      ll.insertLast (8);

      ll.display ();

      ll.printk(4);
  }
}

Output

1 2 3 5 6 7 8 
4th Node from the end is 5