代码如下: 1classNumArray {2int[] dp;3publicNumArray(int[] nums) {4if( nums ==null|| nums.length == 0 )return;5dp =newint[nums.length];6dp[0]=nums[0];7for(inti = 1 ; i < nums.length ; i ++){8dp[i] = dp[i-1]+nums[i];9}10}1112publicintsumRange(inti,intj) {13r...
}intsumRange(inti,intj) {if(i==0)returnsum[j+1];returnsum[j+1]-sum[i]; }private: vector<int>sum; };
Can you solve this real interview question? Range Sum Query 2D - Immutable - Given a 2D matrix matrix, handle multiple queries of the following type: * Calculate the sum of the elements of matrix inside the rectangle defined by its upper left corner (r
You may assume that the array does not change. There are many calls to sumRange function. 解题思路 —— 前缀和 记录下前缀和, 即,PrefixSum[i] 表示前 i 个数字的和。 特别地,当 i = 0 时, PrefixSum[i] = 0。 则...
https://leetcode.com/problems/range-sum-query-immutable/题目: Given an integer array nums, find the sum of the elements between indices i and j (i ≤ j), inclusive. Example: Given nums = [-2, 0, 3, -5, 2, -1] sumRange(0, 2) -> 1 ...
Range Sum Query 2D 上图子矩阵左上角 (row1, col1) = (2, 1) ,右下角(row2, col2) = (4, 3),该子矩形内元素的总和为 8。 示例: 给定matrix = [[3, 0, 1, 4, 2],[5, 6, 3, 2, 1],[1, 2, 0, 1, 5],[4, 1, 0, 1, 7],[1, 0, 3, 0, 5]]sumRegion(2, 1 ...
Golang中如何实现Range Sum Query - Immutable功能? 在Leetcode 303题中,Golang的解法有哪些优化技巧? Golang实现Range Sum Query - Immutable时,时间复杂度是多少? 版权声明:原创勿转 https://cloud.tencent.com/developer/article/1412946 思路 保存一个slice code 代码语言:javascript 代码运行次数:0 运行 AI...
sumRange(0,2) ->1sumRange(2,5) ->-1sumRange(0,5) ->-3批注: 你可以假定这个数组不会改变。 这里会有很多次对sumRange函数的调用。 原文 Given an integer array nums, find the sumofthe elements between indices iandj (i ≤ j), inclusive. ...
range-sum-query-2d-immutable.cpp Go to file 41 lines (35 sloc) 1.08 KB Raw Blame // Time: ctor: O(m * n), // lookup: O(1) // Space: O(m * n) class NumMatrix { public: NumMatrix(vector<vector<int>> &matrix) { if (matrix.empty()) { return; } const auto m = ...
Range Sum Query - Immutable Range Sum Query - Immutable 题目描述 Given an integer array nums, find the sum of the elements between indices 39710 Python之range()函数 三种方法可以调用range()。 (1) range(stop) :输出从0开始到stop-1的整数。...for i in range(3): print(i) #output #0 #1...