15. 3Sum Medium Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Note: The solution set must not contain duplicate triplets. Example: Giv…

LeetCode:Path Sum 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 / \ \…

LeetCode 15 3Sum [sort] <c++> 给出一个一维数组,找出其中所有和为零的三元组(元素集相同的视作同一个三元组)的集合. C++ 先自己写了一发,虽然过了,但跑了308 ms... 我的做法是先排序,扫一遍,处理出unorder_map<0-a[i],i>的hash表.再\(O(n^2)\)枚举前两个元素,查表直接知道第三个元素的位置,然后将三元组加入到答案集合中,通过枚举时添加的限制条件规避重复元素. 复杂度\(O(n^2)\),由于使用了hash表,常数…

题目传送门 /* 二分查找/暴力:先埃氏筛选预处理,然后暴力对于每一行每一列的不是素数的二分查找最近的素数,更新最小值 */ #include <cstdio> #include <cstring> #include <algorithm> using namespace std; ; ; const int INF = 0x3f3f3f3f; int a[MAXN][MAXN]; int mn_r[MAXN]; int mn_c[MAXN]; bool is_prim…

剑指offer 65. 不用加减乘除做加法(Leetcode 371. Sum of Two Integers) https://leetcode.com/problems/sum-of-two-integers/ 题目: 写一个函数,求两个整数之和,要求在函数体内不得使用加减乘除这四个符号. 分析: 对于不能使用正常的四则运算符,一般就是使用位运算了.而本题要想实现加法,只能使用异或了. 需要注意的是,加法的时候涉及进位,而进位的实现利用与运算. 此外,进位之后还有可能产生进位,所以要在循环里…

D. String Game Little Nastya has a hobby, she likes to remove some letters from word, to obtain another word. But it turns out to be pretty hard for her, because she is too young. Therefore, her brother Sergey always helps her. Sergey gives Nastya th…

引用题解:http://hzwer.com/5153.html 当然,二分可以换成哈希表. #include<cstdio> #include<iostream> #include<cstring> using namespace std; #define MOD 2501 typedef unsigned long long ull; const ull seed1=3659,seed2=1789; ull sum[51][51],sum2[51][51],v[MOD…

[题目] Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Note: The solution set must not contain duplicate triplets. Example: Given array nu…

一.题目 给你一个包含 n 个整数的数组 nums,判断 nums 中是否存在三个元素 a,b,c ,使得 a + b + c = 0 ?请你找出所有满足条件且不重复的三元组. 注意:答案中不可以包含重复的三元组. 示例: 给定数组 nums = [-1, 0, 1, 2, -1, -4], 满足要求的三元组集合为: [ [-1, 0, 1], [-1, -1, 2] ] 二.题解 思路1: 之前有道算法题,是求两数之和,所以想法就是先遍历数组,固定当前元素,并求出当前元素的相反数,即剩下两个数…

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 no larger than k. Example: Given matrix = [ [1, 0, 1], [0, -2, 3] ] k = 2 The answer is 2. Because the sum of rectangle [[0, 1], […

Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution. Example: Given nums = [2, 7, 11, 15], target = 9, Because nums[0] + nums[1] = 2…

二分查找篇 # 题名 刷题 通过率 难度 4 两个排序数组的中位数 C#LeetCode刷题之#4-两个排序数组的中位数(Median of Two Sorted Arrays)-该题未达最优解 30.8% 困难 29 两数相除   15.3% 中等 33 搜索旋转排序数组   32.6% 中等 34 在排序数组中查找元素的第一个和最后一个位置   31.9% 中等 35 搜索插入位置 C#LeetCode刷题之#35-搜索插入位置(Search Insert Position) 40.0% 简…

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 update(1, 2…

Given an array of integers that is already sorted in ascending order, 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 mu…

原题链接在这里:https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/ 题目: Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number. The function twoSum should return in…

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 no larger than k. Example: Given matrix = [ [1, 0, 1], [0, -2, 3] ] k = 2 The answer is 2. Because the sum of rectangle [[0, 1], […

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 that…

Find the sum of all left leaves in a given binary tree. Example: 3 / \ 9 20 / \ 15 7 There are two left leaves in the binary tree, with values 9 and 15 respectively. Return 24. 题目标签:Tree 这道题目给了我们一个二叉树,让我们找到所有左子叶之和.这里需要另外一个function - sumLeftLeaves 还要一…

Calculate the sum of two integers a and b, but you are not allowed to use the operator + and -. Example:Given a = 1 and b = 2, return 3. 题目标签:Bit Manipulation 这道题目让我们做两数之和,当然包括负数,而且不能用+,-等符号.所以明显是让我们从计算机的原理出发,运用OR,AND,XOR等运算法则.一开始自己想的如果两个数都是正数,那么很简单,…

Array Two Pointers Binary Search Description: Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers such…

In a given array nums of positive integers, find three non-overlapping subarrays with maximum sum. Each subarray will be of size k, and we want to maximize the sum of all 3*k entries. Return the result as a list of indices representing the starting p…

Implement a MapSum class with insert, and sum methods. For the method insert, you'll be given a pair of (string, integer). The string represents the key and the integer represents the value. If the key already existed, then the original key-value pai…

Given an array of integers and an integer k, you need to find the total number of continuous subarrays whose sum equals to k. Example 1: Input:nums = [1,1,1], k = 2 Output: 2 Note: The length of the array is in range [1, 20,000]. The range of numbers…

We partition a row of numbers A into at most K adjacent (non-empty) groups, then our score is the sum of the average of each group. What is the largest score we can achieve? Note that our partition must use every number in A, and that scores are not…

https://leetcode.com/problems/3sum/ 题目: 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-des…

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…

15. 三数之和 15. 3Sum 题目描述 Given an array nums of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Note: The solution set must not contain duplicate triplets. LeetC…

LeetCode刷题记录 传送门 Description An undirected, connected treewith N nodes labelled 0...N-1 and N-1 edges are given. The ith edge connects nodes edges[i][0] and edges[i][1] together. Return a list ans, where ans[i] is the sum of the distances between nod…

what the fuck! Description 现在有一家公司有nnn个员工(nnn为奇数),他们的工资发放是基本工资+提成,现在这家公司计划再招一批人.要写一篇招聘启事,但是对于这个招聘启事中的薪资具体要写多少犯愁了. 规定招聘启事中薪资为nnn个工人中工资的中位数,为了能更快的招到人,招聘启事中写的薪资越大越好. 现在给出每个人的基本工资,以及可以用来发工资的总钱,你可以自由分配他们的提成(给出的钱可以不用完),让你求出最大的中位数.(保证有答案) Input 第一行两个整数n,sn,…

Two Sum 題目連結 官網題目說明: 解法: 從給定的一組值內找出第一組兩數相加剛好等於給定的目標值,暴力解很簡單(只會這樣= =),兩個迴圈,只要找到相加的值就跳出. /// <summary> /// 暴力解O(n) /// </summary> /// <param name="nums"></param> /// <param name="target"></param> /// &…