DIY: Range Sum Query 2D — Immutable
Explore how to implement and optimize the NumMatrix class in Swift for handling multiple 2D range sum queries on immutable matrices. Understand how to calculate the sum of elements within a specified rectangular region using efficient data structures and methods to support quick queries.
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, ...