Heap pattern
Merge K Sorted Lists
Given an array of k linked lists, each sorted in ascending order, merge them into a single sorted linked list and return its head. Watch it run step by step, then write your own pseudocode and get it checked by AI.
- LeetCode 23
- Hard
- 2 approaches
Sign in with Google or GitHub and you land straight on this page. DSA comes with the all labs plan and every ChaiCode batch.
HeapLeetCode 23
Hard
From the first idea to the best one
- 01 Brute force · scan k heads each round O(N·k)O(1) space
- 02 Optimized · min-heap of heads O(N log k)O(k) space
What you will learn
- How to read Merge K Sorted Lists and spot the heap pattern in it
- Brute force · scan k heads each round: O(N·k) time, O(1) space
- Optimized · min-heap of heads: O(N log k) time, O(k) space
- The pseudocode for each approach, its line lit as the animation runs
- Practice: write your own pseudocode and get it checked
More Heap
See Merge K Sorted Lists run, step by step
Sign in and this page opens on the animation, with all 7 Heap problems beside it.
DSA comes with the all labs plan and every ChaiCode batch.