题意: 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: The solution set must not contain duplicate triplets.  (Medium) For example, given a…

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 nums =…

数组中找三个数和为0的结果集 1 // 解法一:先排序 然后固定一个值 然后用求两个数的和的方式 public static List<List<Integer>> threeSum(int[] nums) { List<List<Integer>> res = new ArrayList<>(); if (nums.length < 3) { return res; } Arrays.sort(nums); // 遍历到倒数第三个就可以了…

给定一个包含 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 ?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. 例如, 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] ] 双指针加去重 class Solution { public: vector<vector<int> > threeSum(…

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…

第六周.后期补完,太忙了. 1.Algorithm:每周至少做一个 leetcode 的算法题2.Review:阅读并点评至少一篇英文技术文章3.Tip:学习至少一个技术技巧4.Share:分享一篇有观点和思考的技术文章 以下是各项的情况: Algorithm 链接:[LeetCode-15]-3sum class Solution { public List<List<Integer>> threeSum(int[] nums) { List<List<Integer…

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 nums =…

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: The solution set must not contain duplicate triplets. For example, given array S = [-1,…

原题重述:(点击图片可以进入来源链接) 这到题目的中文解释是, 输入一个数组,例如{-1 0 1 2 -1 -4},从数组中找三个数(a,b,c),使得其和0,输出所有的(a,b,c)组合. 要求abc不能重复,并且a<=b<=c. 拿到这个题目的时候,其实每个程序猿都能想到如下的算法,也就是暴力破解,其时间复杂度为o(n^3): for(int i=0;i<nums.length;i++){ for(int j=i+1;j<nums.length;j++){ for(int k=…

Given an array of n integers nums and a target, find the number of index triplets i, j, k with 0 <= i < j < k < n that satisfy the condition nums[i] + nums[j] + nums[k] < target. For example, given nums = [-2, 0, 1, 3], and target = 2. Retu…

Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution. For example, given array S = {-1 2…

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 an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution. For example, given array S = {-1 2…

3Sum Closest Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution. For example, given arr…

题目: Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution. For example, given array S = {-…

Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution. For example, given array S = {-1 2…

问题: Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target.Return the sum of the three integers. You may assume that each input would have exactly one solution.For example, given array S = {-1…

问题: 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: The solution set must not contain duplicate triplets.For example, given array S = [-1,…

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. Notice Elements in a triplet (a,b,c) must be in non-descending order. (ie, a ≤ b ≤ c) The solu…

原题链接在这里:https://leetcode.com/problems/3sum-smaller/ 题目: Given an array of n integers nums and a target, find the number of index triplets i, j, k with 0 <= i < j < k < n that satisfy the condition nums[i] + nums[j] + nums[k] < target. For e…

3Sum 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…

16. 3Sum Closest Total Accepted: 86565 Total Submissions: 291260 Difficulty: Medium Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume…

15. 3Sum Total Accepted: 131800 Total Submissions: 675028 Difficulty: Medium 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: The solutio…

15. 3Sum 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: The solution set must not contain duplicate triplets. For example, given array…

Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. Notice You may assume that each input would have exactly one solution. Example For example, given a…

3Sum Closest Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution. For example, given arr…

3Sum 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…

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…

2sum 如果数组是无序的,先排序(n*logn),然后用两个指针i,j,各自指向数组的首尾两端,令i=0,j=n-1,然后i++,j--,逐次判断a[i]+a[j]?=sum,如果某一刻a[i]+a[j]>sum,则要想办法让sum 的值减小,所以此刻i 不动,j--,如果某一刻a[i]+a[j]<sum,则要想办法让sum 的值增大,所以此刻i++,j 不动.所以,数组无序的时候,时间复杂度最终为O(n*logn+n)=O(n*logn),若原数组是有序的,则不需要事先的排序,直接O(n)…

转自  http://tech-wonderland.net/blog/summary-of-ksum-problems.html 前言: 做过leetcode的人都知道, 里面有2sum, 3sum(closest), 4sum等问题, 这些也是面试里面经典的问题, 考察是否能够合理利用排序这个性质, 一步一步得到高效的算法. 经过总结, 本人觉得这些问题都可以使用一个通用的K sum求和问题加以概括消化, 这里我们先直接给出K Sum的问题描述和算法(递归解法), 然后将这个一般性的方法套用…