Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue. Here, we will use the integers 0, 1, and 2 to represent the color red, white, and bl…

Sort Colors Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue. Here, we will use the integers 0, 1, and 2 to represent the color red, w…

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 计数排序 双指针 日期 题目地址:https://leetcode.com/problems/sort-colors/description/ 题目描述 Given an array with n objects colored red, white or blue, sort them so that objects of the same col…

题目如下: 解题思路:我的解题思路是遍历数组,遇到0删除该元素并插入到数组头部,遇到1则不处理,遇到2删除该元素并插入到数组尾部. 代码如下: class Solution(object): def sortColors(self, nums): """ :type nums: List[int] :rtype: void Do not return anything, modify nums in-place instead. """ inx…

题目如下: 解题思路:本题和[leetcode]75. Sort Colors类似,但是没有要求在输入数组本身修改,所以难度降低了.引入一个新的数组,然后遍历输入数组,如果数组元素是是偶数,插入到新数组头部,否则追加到尾部. 代码如下: class Solution(object): def sortArrayByParity(self, A): """ :type A: List[int] :rtype: List[int] """ res =…

链接:https://leetcode.com/tag/sort/ [56]Merge Intervals (2019年1月26日,谷歌tag复习) 合并区间 Input: [[1,3],[2,6],[8,10],[15,18]] Output: [[1,6],[8,10],[15,18]] Explanation: Since intervals [1,3] and [2,6] overlaps, merge them into [1,6]. 题解:先按照interval的begin从小到大s…

一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white a…

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 库函数排序 桶排序 红黑树排序 归并排序 快速排序 日期 题目地址:https://leetcode.com/problems/sort-an-array/ 题目描述 Given an array of integers nums, sort the array in ascending order. Example 1: Input: [5,2,3…

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 使用奇偶数组 排序 奇偶数位置变量 日期 题目地址: https://leetcode.com/problems/sort-array-by-parity-ii 题目描述 Given an array A of non-negative integers, half of the integers in A are odd, and half of…

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 优先级队列 排序 日期 题目地址:https://leetcode.com/problems/sort-characters-by-frequency/description/ 题目描述 Given a string, sort it in decreasing order based on the frequency of character…

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 日期 题目地址:https://leetcode.com/problems/sort-list/description/ 题目描述 Sort a linked list in O(n log n) time using constant space complexity. Example 1: Input: 4->2->1->3 Output…

Sort a linked list using insertion sort. 思路: 用插入排序对链表排序.插入排序是指每次在一个排好序的链表中插入一个新的值. 注意:把排好序的部分和未排序的部分完全分开,指针不要有交叉. 即不会通过->next 重叠 class Solution { public: ListNode *insertionSortList(ListNode *head) { if(head == NULL) return NULL; ListNode * ans = hea…

Sort a linked list in O(n log n) time using constant space complexity. 链表排序可以用很多方法,插入,冒泡,选择都可以,也容易实现,但是复杂度不符合题意要求. 然后时间复杂度在O(nlogn)的排序算法中,堆排序,快速排序,归并排序. 堆排序,主要是基于数组的,这里是链表,实现起来比较麻烦. 快速排序,快速排序最坏情况的时间复杂度是O(n2) 归并排序,在对数组的归并排序中,是有O(n)的空间复杂度的,但是链表可以不需要,我们…

Sort a linked list using insertion sort. //用到O(N)的额外空间 public class Solution { public ListNode insertionSortList(ListNode head) { if(head==null||head.next==null) return head; ListNode root = new ListNode(head.val); ListNode cur = head.next; while(cur…

题目如下: Given an array of integers nums, sort the array in ascending order. Example 1: Input: [5,2,3,1] Output: [1,2,3,5] Example 2: Input: [5,1,1,2,0,0] Output: [0,0,1,1,2,5] Note: 1 <= A.length <= 10000 -50000 <= A[i] <= 50000 解题思路:题目没说不能用系统函数…

Given a string s, sort it in decreasing order based on the frequency of the characters. The frequency of a character is the number of times it appears in the string. Return the sorted string. If there are multiple answers, return any of them. 考察了map的…

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 自定义sorted函数的cmp 日期 题目地址:https://leetcode.com/problems/sort-array-by-parity/description/ 题目描述: Given an array A of non-negative integers, return an array consisting of all the…

题目如下: 解题思路:非常简单的题目,引入两个变量oddInx = 1和evenInx = 0,和与A等长的结果数组res.然后遍历A,如果A[i]为偶数,则令res[evenInx] = A[i],evenInx += 2:否则令res[oddInx] = A[i],evenInx += 2. 代码如下: class Solution(object): def sortArrayByParityII(self, A): """ :type A: List[int] :rty…

[LeetCode]147. Insertion Sort List 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.me/ 题目地址:https://leetcode.com/problems/insertion-sort-list/description/ 题目描述: Sort a linked list using insertion sort. A graphical…

Algorithm [leetcode]893. Groups of Special-Equivalent Strings https://leetcode.com/problems/groups-of-special-equivalent-strings/ 1)problem You are given an array A of strings. Two strings S and T are special-equivalent if after any number of moves,…

写在前面   老粉丝可能知道现阶段的LeetCode刷题将按照某一个特定的专题进行,之前的[贪心算法]已经结束,虽然只有三个题却包含了简单,中等,困难这三个维度,今天介绍的是第二个专题[数组] 数组(Array)是一种线性表数据结构.它用一组连续的内存空间,来存储一组具有相同类型的数据.在每一种编程语言中,基本都会有数组这种数据类型.不过,它不仅仅是一种编程语言中的数据类型,还是一种最基础的数据结构. 贪心算法回顾: [LeetCode]贪心算法--买卖股票的最佳时机II(122) [LeetC…

全排列问题.经常使用的排列生成算法有序数法.字典序法.换位法(Johnson(Johnson-Trotter).轮转法以及Shift cursor cursor* (Gao & Wang)法. [题目] Given a collection of numbers, return all possible permutations. For example, [1,2,3] have the following permutations: [1,2,3], [1,3,2], [2,1,3], [2…

[题目] Given a collection of numbers that might contain duplicates, return all possible unique permutations. For example, [1,1,2] have the following unique permutations: [1,1,2], [1,2,1], and [2,1,1]. [解析] 题意:求一个数组的全排列.与[LeetCode]Permutations 解题报告 不同的是…

题目等级:4Sum(Medium) 题目描述: 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. Note: The solution se…

题目等级:3Sum(Medium) 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. Exam…

题目如下: 解题思路:本题是[leetcode]473. Matchsticks to Square的姊妹篇,唯一的区别是[leetcode]473. Matchsticks to Square指定了分成四个子数组,而本题分成的份数不定,作为参数输入.另外,本题的测试用例好像复杂一点,因此我过滤掉了nums中值等于avg的元素,不参与后面的DFS计算,提高效率. 代码如下: class Solution(object): def canPartitionKSubsets(self, nums,…

目录 二分查找 排序的写法 BFS的写法 DFS的写法 回溯法 树 递归 迭代 前序遍历 中序遍历 后序遍历 构建完全二叉树 并查集 前缀树 图遍历 Dijkstra算法 Floyd-Warshall算法 Bellman-Ford算法 最小生成树 Kruskal算法 Prim算法 拓扑排序 双指针 动态规划 状态搜索 贪心 本文的目的是收集一些典型的题目,记住其写法,理解其思想,即可做到一通百通.欢迎大家提出宝贵意见! 博主有算法题解的微信公众号啦,欢迎关注「负雪明烛」,持续更新算法题的解题思路…

[LeetCode]Longest Word in Dictionary through Deleting 解题报告 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/longest-word-in-dictionary-through-deleting/#/description 题目描述: Given a string and a string dictionary, find the longest string in the di…

[LeetCode]Largest Number 解题报告 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/largest-number/#/description 题目描述: Given a list of non negative integers, arrange them such that they form the largest number. For example, given [3, 30, 34, 5, 9], t…

[LeetCode]881. Boats to Save People 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/boats-to-save-people/description/ 题目描述: The i-th person has weight people[i], and each boat can carry a maximu…