James Pan

原题网址：https://leetcode.com/problems/count-of-range-sum/Given an integer array nums, return the number of range sums that lie in [lower, upper] inclusive.Range sum S(i, j) is defined as the su

原题网址：https://leetcode.com/problems/range-addition/Assume you have an array of length n initialized with all 0's and are given k update operations.Each operation is represented as a triplet: 

原题网址：https://leetcode.com/problems/max-sum-of-sub-matrix-no-larger-than-k/Given a non-empty 2D matrix matrix and an integer k, find the max sum of a rectangle in the matrix such that its sum is