Plain English Leetcode - 25 Reverse Nodes in k-Group

Sun, 28 Aug 2022 14:22:55 +0800

25. Reverse Nodes in k-Group

https://leetcode.com/problems/reverse-nodes-in-k-group/

Hard

Given the head of a linked list, reverse the nodes of the list k at a time, and return the modified list.

k is a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple of k then left-out nodes, in the end, should remain as it is.

You may not alter the values in the list's nodes, only nodes themselves may be changed.

Plain English Leetcode - 23 Merge k Sorted Lists

Sat, 25 Jun 2022 23:29:46 +0800

23. Merge k Sorted Lists

https://leetcode.com/problems/merge-k-sorted-lists/

Hard

You are given an array of k linked-lists lists, each linked-list is sorted in ascending order.

Merge all the linked-lists into one sorted linked-list and return it.

Example 1:

Input: lists = [[1,4,5],[1,3,4],[2,6]]
Output: [1,1,2,3,4,4,5,6]
Explanation: The linked-lists are:
[
  1->4->5,
  1->3->4,
  2->6
]
merging them into one sorted list:
1->1->2->3->4->4->5->6

Example 2:

Input: lists = []
Output: []

Example 3:

Input: lists = [[]]
Output: []

Leetcode-Hard on Alan Zhan Blog

Plain English Leetcode - 25 Reverse Nodes in k-Group

25. Reverse Nodes in k-Group

Hard

Plain English Leetcode - 23 Merge k Sorted Lists

23. Merge k Sorted Lists

Hard