# Reverse k nodes in linked list

## Problem

Reverse every k nodes in a linked list and return the head appropriately.

## Solution

We will use a reverse function which reverses k nodes from head and return kth node as head. We will use this function recursively to reverse every k nodes.

## Code

public class ReverseKNodes { public static void main(String[] args) { int[] arr = { 4, 5, 3, 6, 8, 3, 5, 7, 3, 7, 9, 4, 6 }; Node head = createLinkedList(arr); printLinkedList(head); head = reverse(head, 4); printLinkedList(head); } static Node reverse(Node head, int k) { Node current = head; Node next = null; Node prev = null; int count = 0; while (current != null && count < k) { next = current.next; current.next = prev; prev = current; current = next; count++; } if (next != null) { head.next = reverse(next, k); } return prev; } private static void printLinkedList(Node head) { while (head != null) { System.out.print(head.value + "->"); head = head.next; } System.out.println(); } private static Node createLinkedList(int[] arr) { Node head = null; Node current = null; for (int element : arr) { if (head == null) { head = new Node(element); current = head; } else { current.next = new Node(element); current = current.next; } } return head; } static class Node { public Node next; public int value; public Node(int value) { this.value = value; } } }