Top K Frequent Elements — Count, Then Skip the Sort (LeetCode 347)

Top K Frequent Elements — Count, Then Skip the Sort (LeetCode 347)

In this deep-dive we solve LeetCode 347 step-by-step: given an array of integers and an integer k, return the k most frequent elements in any order.

Key insights:
• Count frequencies with a hash map — O(n)
• Use bucket sort (array of buckets) instead of sorting — O(n) instead of O(n log n)
• Why bucket sort works: frequency range is bounded 1 to n

We build intuition from the naive approach (sort by frequency) and show how bucket sort avoids the logarithmic cost. Walk through a complete example to see the algorithm in action.

Perfect for interview prep, competitive programming, and mastering hash map + frequency-counting patterns.

Concepts: hash maps, counting, bucket sort, top k elements, arrays and hashing

#LeetCode #DSA #CodingInterview

Видео Top K Frequent Elements — Count, Then Skip the Sort (LeetCode 347) канала Unrote