题目: Given an array of integers, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2. Please note t…

前言   [LeetCode 题解]系列传送门:  http://www.cnblogs.com/double-win/category/573499.html   1.题目描述 Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example…

链接 4Sum 难度 Medium 描述 Given an array nums of n integers and an integer target, are there elements a , b , c , and d in nums such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target. 给定一个n个整数的数组n,和一个整数tar…

题目链接 链接:https://leetcode.com/problems/max-sum-of-rectangle-no-larger-than-k/description/ 题解&代码 1.暴力枚举所有的情况,时间复杂度O(n^2*m^2),实际耗时759 ms class Solution { public: int maxSumSubmatrix(vector<vector<int> >& matrix, int k) { int n=matrix.size…

Given a 2D matrix matrix, find the sum of the elements inside the rectangle defined by its upper left corner (row1, col1) and lower right corner (row2, col2). Example: Given matrix = [ [3, 0, 1, 4, 2], [5, 6, 3, 2, 1], [1, 2, 0, 1, 5], [4, 1, 0, 1, 7…

Given nums = [-2, 0, 3, -5, 2, -1] sumRange(0, 2) -> 1 sumRange(2, 5) -> -1 sumRange(0, 5) -> -3 Note: You may assume that the array does not change. There are many calls to sumRange function. 求区域和,而且这个和也有可能被多次的调用,所以不能使用直接计算的方法,用dp解决,注意0这个点的特殊情况就…

Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Note: Elements in a triplet (a,b,c) must be in non-descending order. (ie, a ≤ b ≤ c) The solut…

Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ / \ 7 2 5 1 return [ [5,4,11,2], [5,8,4,5] ] 求路径的和与某一特定的值时候对等即可,简…

Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 要求求出是否有一条路径…

一. 题目描写叙述 Given an integer array nums, find the sum of the elements between indices i and j (i ≤ j), inclusive. The update(i, val) function modifies nums by updating the element at index i to val. Example: Given nums = [1, 3, 5] sumRange(0, 2) -> 9 u…