Continuous Subarray Sum II   Given an circular integer array (the next element of the last element is the first element), find a continuous subarray in it, where the sum of numbers is the biggest. Your code should return the index of the first number…

Given an integer array, find a continuous rotate subarray where the sum of numbers is the biggest. Your code should return the index of the first number and the index of the last number. (If their are duplicate answer, return anyone. The answer can b…

1. 原题链接 https://leetcode.com/problems/combination-sum-ii/description/ 2. 题目要求 给定一个整型数组candidates[ ]和目标值target,找出数组中累加之后等于target的所有元素组合 注意:(1)每个可能的答案中,数组中的每一个元素只能使用一次:(2)数组存在重复元素:(3)数组中都是正整数:(4)不能存在重复解 3. 解题思路 这与第39题 Combination Sum 看起来很是类似,但一些细节要求完全不…

Description Given an circular integer array (the next element of the last element is the first element), find a continuous subarray in it, where the sum of numbers is the biggest. Your code should return the index of the first number and the index of…

Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. Each number in C may only be used once in the combination. Note: All numbers (including target) will be posi…

题意: 给一棵二叉树,每个叶子到根的路径之和为sum的,将所有可能的路径装进vector返回. 思路: 节点的值可能为负的.这样子就必须到了叶节点才能判断,而不能中途进行剪枝. /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL)…

题意: 在集合candidates中选出任意多个元素,使得他们的和为target,返回所有的组合,以升序排列. 思路: 难点在于如何去重,比如集合{1,1,2},target=3,那么只有一个组合就是1+2=3,而不是两个. DFS解决,每次考虑candidates[i]取还是不取,但是这样子还是会产生重复,这里只需要一个技巧就可以使得没有重复出现.如果当前元素已经被考虑过取了,那么在考虑不取的时候,i后面的与candidates[i]相同的都要跳过.观察一下可以发现,如果有一串相同的数字出现的…

题目: 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] ] 思路: 递归求解,只是要保存当前…

Single Number II Given 3*n + 1 numbers, every numbers occurs triple times except one, find it. Example Given [1,1,2,3,3,3,2,2,4,1] return 4 Challenge One-pass, constant extra space. 统计每一位上的1出现的次数,然后模3 , 题目上的3 * n + 1给了提示,然后又做过一题2 * n + 1的位操作. public…

LintCode 402: Continuous Subarray Sum 题目描述 给定一个整数数组,请找出一个连续子数组,使得该子数组的和最大.输出答案时,请分别返回第一个数字和最后一个数字的下标.(如果两个相同的答案,请返回其中任意一个) 样例 给定[-3, 1, 3, -3, 4], 返回[1,4]. Thu Feb 23 2017 思路 本题有很多解法,最巧妙的解法就是一遍扫描记忆的方法了,时间复杂度为\(O(n)\). 用一个变量记录连续累加的和,当和为负数时,变量清零,从下一个数字…