1.题目大意 Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at a random position. Find the letter that was added in t. Example: Input: s = "abcd" t = &…

[LeetCode]331. Verify Preorder Serialization of a Binary Tree 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/verify-preorder-serialization-of-a-binary-tree/description/ 题目描述: One way to serialize a binary tree is to use pre-order traver…

[LeetCode]863. All Nodes Distance K in Binary Tree 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/all-nodes-distance-k-in-binary-tree/description/ 题目描述: We are given a binary tree (with root no…

[LeetCode]378. Kth Smallest Element in a Sorted Matrix 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/kth-smallest-element-in-a-sorted-matrix/description/ 题目描述: Given a n x n matrix where each of the rows and columns are sorted in ascen…

[LeetCode]154. Find Minimum in Rotated Sorted Array II 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/description/ 题目描述: Follow up for "Find Minimum in Rotated Sorted Array": What if duplicat…

[LeetCode]109. Convert Sorted List to Binary Search Tree 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/convert-sorted-list-to-binary-search-tree/description/ 题目描述: Given a s…

[LeetCode]452. Minimum Number of Arrows to Burst Balloons 解题报告(Python) 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/description/ 题目描述: There are a number of spherical balloons spread in two-dimensio…

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/lowest-common-ancestor-of-a-binary-tree/description/ 题目描述 Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in…

转载地址 https://www.cnblogs.com/AlvinZH/p/8527668.html#_label5 题目详情 给定一个字符串,你的任务是计算这个字符串中有多少个回文子串. 具有不同开始位置或结束位置的子串,即使是由相同的字符组成,也会被计为是不同的子串. 示例 1: 输入: "abc" 输出: 3 解释: 三个回文子串: "a", "b", "c". 示例 2: 输入: "aaa" 输出…

Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at a random position. Find the letter that was added in t. Example: Input: s = "abcd" t = "ab…

Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at a random position. Find the letter that was added in t. Example: Input: s = "abcd" t = "ab…

Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at a random position. Find the letter that was added in t. Example: Input: s = "abcd" t = "ab…

题目要求 Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at a random position. Find the letter that was added in t. 题目分析及思路 给定两个只由小写字母组成的字符串s和t,其中t是在s字符串组成…

题目: Given two strings s and t which consist of only lowercase letters. String t is generated by random shuffling string s and then add one more letter at a random position. Find the letter that was added in t. Example: Input: s = "abcd" t = &quo…

上篇介绍了隐马尔科夫模型 本文给出关于问题3解决方法,并给出一个例子的python代码 回顾上文,问题3是什么, 下面给出,维比特算法(biterbi) algorithm 下面通过一个具体例子,来说明维比特算法(biterbi) 下面附上该解决该例题的python代码 import numpy as np #you must install the numpy A=np.array([[0.5,0.2,0.3],[0.3,0.5,0.2],[0.2,0.3,0.5]]) B=np.array(…

题目 题目链接 Given a non-empty string check if it can be constructed by taking a substring of it and appending multiple copies of the substring together. You may assume the given string consists of lowercase English letters only and its length will not ex…

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 方法一:暴力求解 方法二:原地变负做标记 方法三:使用set 日期 [LeetCode] 题目地址:https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/ Total Accepted: 14302 Total Submissions: 24993 Difficulty:…

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 BFS 日期 题目地址:https://leetcode.com/problems/maximum-level-sum-of-a-binary-tree/ 题目描述 Given the root of a binary tree, the level of its root is 1, the level of its children is 2, 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 Java解法 Python解法 C++ 解法 日期 [LeetCode] 题目地址:https://leetcode.com/problems/best-time-to-buy-and-sell-stock/ Total Accepted: 98941 Total Submissions: 274449 Difficulty: Easy 题目描述 S…

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/triples-with-bitwise-and-equal-to-zero/ 题目描述 Given an array of integers A, find the number of triples of indices (i, j, k) such that: 0 <=…

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 方法一:BFS 方法二:DFS 日期 题目地址:https://leetcode.com/problems/two-sum-iv-input-is-a-bst/description/ 题目描述 Given a Binary Search Tree and a target number, return true if there exist two…

题目要求 Given an array A of integers, return true if and only if we can partition the array into three non-empty parts with equal sums. Formally, we can partition the array if we can find indexes i+1 < j with (A[0] + A[1] + ... + A[i] == A[i+1] + A[i+2]…

Find Minimum in Rotated Sorted Array II Follow up for "Find Minimum in Rotated Sorted Array":What if duplicates are allowed? Would this affect the run-time complexity? How and why?Suppose a sorted array is rotated at some pivot unknown to you be…

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 DFS 日期 题目地址:https://leetcode.com/problems/sum-of-root-to-leaf-binary-numbers/ 题目描述 Given a binary tree, each node has value 0 or 1. Each root-to-leaf path represents a binary n…

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/capacity-to-ship-packages-within-d-days/ 题目描述 A conveyor belt has packages that must be shipped from one port to another within D days. Th…

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 递归 日期 题目地址:https://leetcode.com/problems/construct-binary-search-tree-from-preorder-traversal/ 题目描述 Return the root node of a binary search tree that matches the given preorder…

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 小根堆 日期 题目地址:https://leetcode.com/problems/maximize-sum-of-array-after-k-negations/ 题目描述 Given an array A of integers, we must modify the array in the following way: we choose 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 循环 日期 题目地址:https://leetcode.com/problems/check-if-word-is-valid-after-substitutions/ 题目描述 We are given that the string "abc" is valid. From any valid string V, we may spli…

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 DFS BFS 日期 题目地址:https://leetcode.com/problems/vertical-order-traversal-of-a-binary-tree/ 题目描述 Given a binary tree, return the vertical order traversal of its nodes values. For…

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 前序遍历 日期 题目地址:https://leetcode.com/problems/flip-binary-tree-to-match-preorder-traversal/ 题目描述 Given a binary tree with N nodes, each node has a different value from {1, -, N}.…