Given an array of integers, 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements that appear twice in this array. Could you do it without extra space and in O(n) runtime? Example: Input: [4,3,2,7,…

后面3个题都是限制在1-n的,所有可以不先排序,可以利用巧方法做.最后两个题几乎一模一样. 217. Contains Duplicate class Solution { public: bool containsDuplicate(vector<int>& nums) { int length = nums.size(); ) return false; sort(nums.begin(),nums.end()); ;i < length;i++){ ]) return tr…

Question 442. Find All Duplicates in an Array Solution 题目大意:在数据中找重复两次的数 思路:数组排序,前一个与后一个相同的即为要找的数 Java实现: public List<Integer> findDuplicates(int[] nums) { List<Integer> ans = new ArrayList<>(); if (nums.length == 0) return ans; Arrays.so…

Given an array of integers, 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements that appear twice in this array. Could you do it without extra space and in O(n) runtime? Example: Input: [4,3,2,7,…

［抄题］: Given an array of integers, 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements that appear twice in this array. Could you do it without extra space and in O(n) runtime? Example: Input: [4,…

https://leetcode.com/problems/find-all-duplicates-in-an-array/ 一列数,1 ≤ a[i] ≤ n (n = size of array),有的出现一次有的出现两次,输出出现两次的数. Example: Input: [4,3,2,7,8,2,3,1] Output: [2,3] 耿直的你大概会写出如下代码 class Solution(object): def findDuplicates(self, nums): myset=set…

https://leetcode.com/problems/find-all-duplicates-in-an-array/description/ 参考:http://www.cnblogs.com/grandyang/p/4843654.html Given an array of integers, 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all th…

题目 题目链接 Given an array of integers, 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements that appear twice in this array. Could you do it without extra space and in O(n) runtime? Example: Input: […

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 字典 原地变负 日期 题目地址:https://leetcode.com/problems/find-all-duplicates-in-an-array/description/ 题目描述 Given an array of integers, 1 ≤ a[i] ≤ n (n = size of array), some elements appe…

给定一个整数数组 a,其中1 ≤ a[i] ≤ n (n为数组长度), 其中有些元素出现两次而其他元素出现一次.找到所有出现两次的元素.你可以不用到任何额外空间并在O(n)时间复杂度内解决这个问题吗?示例:输入:[4,3,2,7,8,2,3,1]输出:[2,3]详见:https://leetcode.com/problems/find-all-duplicates-in-an-array/description/ C++: 方法一: class Solution { public: vector…