LeetCode | Maximum Subarray Sum With Length Divisible by K | C++ | Golang | Rust
Автор: AlgorithmsUntilRED
Загружено: 2025-11-27
Просмотров: 65
LeetCode 3381 – Maximum Subarray Sum With Length Divisible by K
In this video, I break down LeetCode 3381 – Maximum Subarray Sum With Length Divisible by K from absolute basics to the fully optimized solution.
We start with the brute-force idea, move to the prefix-sum O(n²) approach, and then uncover the hidden insight behind the index modulo relationship.
Once the intuition clicks, we build an O(n) solution by tracking minimum prefix sums for each modulo class.
I also explain why (j - i) % k == 0 implies j % k == i % k, how to visualize remainder groups, and how to convert this into a clean prefix-sum optimization.
Finally, I implement the solution in C++, Golang, and Rust, covering edge cases and common pitfalls (like zero-length subarrays, unset values, and negative prefix sums).
If you're preparing for interviews or improving your competitive programming skills, this walkthrough will help you build strong intuition for prefix techniques and modular constraints.
⏱ Timestamps
00:00 – Problem Breakdown & Logic
07:00 – Logic behind indices
15:50 – Logic behind least prefix sum
22:45 – Dry run of Algorithm
31:34 – C++ Implementation
40:25 – Golang Implementation
43:22 – Rust Implementation
Доступные форматы для скачивания:
Скачать видео mp4
-
Информация по загрузке:
