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Reverse every K-element Sub-list (medium)

Reverse every K-element Sub-list (medium)

Problem Statement

Given the head of a LinkedList and a number ‘k’, reverse every ‘k’ sized sub-list starting from the head.

If, in the end, you are left with a sub-list with less than ‘k’ elements, reverse it too.

Try it yourself

Try solving this question here:

import java.util.*;
class ListNode {
  int value = 0;
  ListNode next;
  ListNode(int value) {
    this.value = value;
  }
}
class ReverseEveryKElements {
  public static ListNode reverse(ListNode head, int k) {
    // TODO: Write your code here
    return head;
  }
  public static void main(String[] args) {
    ListNode head = new ListNode(1);
    head.next = new ListNode(2);
    head.next.next = new ListNode(3);
    head.next.next.next = new ListNode(4);
    head.next.next.next.next = new ListNode(5);
    head.next.next.next.next.next = new ListNode(6);
    head.next.next.next.next.next.next = new ListNode(7);
    head.next.next.next.next.next.next.next = new ListNode(8);
    ListNode result = ReverseEveryKElements.reverse(head, 3);
    System.out.print("Nodes of the reversed LinkedList are: ");
    while (result != null) {
      System.out.print(result.value + " ");
      result = result.next;
    }
  }
}

Solution

The problem follows the In-place Reversal of a LinkedList pattern and is quite similar to ...