Nth node from end of linked list Java

PROGRAM TO GET Nth NODE FROM END OF LINKED LIST

class LinkedList 

{

    Node head; // head of the list

  

    /* Linked List node */

    class Node {

        int data;

        Node next;

        Node(int d)

        {

            data = d;

            next = null;

        }

    }

  

    /* Function to get the 

      nth node from end of list */

    void printNthFromLast(int n)

    {

        Node main_ptr = head;

        Node ref_ptr = head;

  

        int count = 0;

        if (head != null) 

        {

            while (count < n) 

            {

                if (ref_ptr == null) 

                {

                    System.out.println(n 

                     + " is greater than the no "

                       + " of nodes in the list");

                    return;

                }

                ref_ptr = ref_ptr.next;

                count++;

            }

  

            if(ref_ptr == null)

            {

              head = head.next;

              if(head != null)

                System.out.println("Node no. " + n +

                                   " from last is " + 

                                      head.data);

            }

            else

            {

                    

              while (ref_ptr != null) 

              {

                  main_ptr = main_ptr.next;

                  ref_ptr = ref_ptr.next;

              }

              System.out.println("Node no. " + n +

                                " from last is " +

                                  main_ptr.data);

            }

        }

    }

  

    /* Inserts a new Node at front of the list. */

    public void push(int new_data)

    {

        /* 1 & 2: Allocate the Node &

                  Put in the data*/

        Node new_node = new Node(new_data);

  

        /* 3. Make next of new Node as head */

        new_node.next = head;

  

        /* 4. Move the head to point to new Node */

        head = new_node;

    }

  

    /*Driver program to test above methods */

    public static void main(String[] args)

    {

        LinkedList llist = new LinkedList();

        llist.push(20);

        llist.push(4);

        llist.push(15);

        llist.push(35);

  

        llist.printNthFromLast(4);

    }

} 




OUTPUT

Node no. 4 from last is 35 

CREDITS: https://www.geeksforgeeks.org/nth-node-from-the-end-of-a-linked-list/