Find kth element from last in a singly linked list, Java

Find kth element from last in a singly linked list

/**
 *  Given a singly linked list, find kth element from last.
 *
 *  @author: Jayesh Chandrapal
 */

import java.util.*;
import java.lang.*;

class Node {
    int data;
    Node next;
    
    Node(int data, Node next) {
        this.data = data;
        this.next = next;
    }
}

class Rextester
{  
    public static void main(String args[])
    {
        Node mylist = new Node(10, new Node(20, new Node(30, new Node(40, new Node(50, new Node(60, new Node(70, null)))))));

int k = 2;
        Node kth = getElementFromLast(mylist, k);
        
        if(kth != null) {
            System.out.format("\n%dth element from last = %d\n", k, kth.data);
        } else {
            System.out.println("Incorrect index entered!");
        }
    }
    
    public static Node getElementFromLast(Node head, int k) {
        if(k < 0) {
            return null;
        }
        
        Node current = head;
        Node kth = head;
        int index = 0;
        
        while(current != null) {
            if(index >= k) {
                kth = kth.next;
            }
            
            current = current.next;
            
            index++;
        }
        
        if(index < k)
            return null;
        
        return kth;
    }
}


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