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Leetcode 308. Range Sum Query 2D - Mutable
Design a data structure that supports point updates and returns the sum of any submatrix in a 2D matrix, optimizing for many interleaved update and sumRegion operations. Expect to use a dynamic 2D structure (e.g., 2D BIT or 2D segment tree) to achieve much better than O(mn) per operation — typically logarithmic time per update/query.
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Moloco
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Early October, 2025
Moloco
Staff
Follow-up: a. Implement caching for the query method. This method takes the corner coordinates as input. b. Enhance caching to support heavy write. The write is performed in a specific cell( takes row and column as input).
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