DIY: Range Sum Query 2D — Immutable
Explore how to implement the NumMatrix class to handle multiple sum queries efficiently on a 2D immutable matrix. Learn to calculate sums of subregions by defining upper left and lower right coordinates. This lesson enhances your ability to solve matrix sum queries common in coding interviews.
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, ...