DIY: Range Sum Query 2D — Immutable
Understand how to design and implement a NumMatrix class in C++ that handles multiple sum queries on a 2D matrix efficiently. Explore techniques to precompute sums for constant-time queries within specified submatrix boundaries.
We'll cover the following...
We'll cover the following...
Problem statement
Given an m * n matrix, you need to handle multiple queries of the following type:
Calculate the sum of the elements of the matrix inside the rectangle defined by its upper left corner, ...