This article explains LeetCode problem 1749, which asks for the subarray with the maximum absolute sum, and shows how prefix sums reduce the task to tracking minimum and maximum prefix values, providing full reference implementations in Java, C++, Python, and TypeScript.
This article first highlights Ctrip's employee benefits, then presents the LeetCode 560 subarray sum problem with detailed explanations and multi-language implementations using prefix sum and hash map, including Java, C++, Python, and TypeScript solutions, and discusses time and space complexities.
The article first critiques a hiring manager’s salary‑balance rationale for a 985‑master candidate, then presents LeetCode problem 1546 on finding the maximum number of non‑overlapping subarrays whose sums equal a target, explaining the solution using prefix sums and providing Java and C++ implementations.
This article explains LeetCode problem 1546, which requires finding the maximum number of non‑empty, non‑overlapping subarrays whose sums equal a given target, discusses why a sliding‑window fails, and provides a prefix‑sum map solution with full Java and C++ implementations.
This article explains the concept of prefix sums, demonstrates how to build and use a prefix‑sum array in PHP with clear code examples, and discusses when the technique is advantageous and its limitations, enabling O(1) interval sum queries after an O(n) preprocessing step.
This article explains how a Fenwick (Binary Indexed) Tree stores prefix sums using binary representations and the least‑significant‑bit trick, shows concrete examples for computing sums of sub‑arrays, and provides a full Python implementation with update and query operations.
