Scramble String Given a string s1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively. Below is one possible representation of s1 = "great": great / \ gr eat / \ / \ g r e at / \ a t To scramble the s…

Given a string s1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively. Below is one possible representation of s1 = "great": great / \ gr eat / \ / \ g r e at / \ a t To scramble the string, we may ch…

[3]Longest Substring Without Repeating Characters (2019年1月22日,复习) [5]Longest Palindromic Substring (2019年1月22日,复习) [6]ZigZag Conversion (2019年1月22日,复习) [8]String to Integer (atoi) (2019年1月22日,复习) [10]Regular Expression Matching (2019年1月22日,复习) [12]In…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 公众号:负雪明烛 本文关键词:字符串转整数,atoi,题解,Leetcode, 力扣,Python, C++, Java 目录 题目描述 题目大意 解题方法 代码 日期 题目地址:https://leetcode-cn.com/problems/string-to-integer-atoi/ 题目描述 Implement the myAtoi(string s) function, 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 字符串构造 日期 题目地址:https://leetcode.com/problems/string-without-aaa-or-bbb/ 题目描述 Given two integers A and B, return any string S such that: S has length A + B and contains exactly A…

Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2. For example,Given:s1 = "aabcc",s2 = "dbbca", When s3 = "aadbbcbcac", return true.When s3 = "aadbbbaccc", return false. 思路:做过几道动态规划了,终于也有了…

Interleaving String Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2. For example,Given:s1 = "aabcc",s2 = "dbbca", When s3 = "aadbbcbcac", return true.When s3 = "aadbbbaccc", return false…

题目: Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended for this problem to be…

题目描述: Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended for this problem to…

problem 443. String Compression Input ["a","a","b","b","c","c","c"] Output ["a","a","b","b","c","c"] Expected ["] a: Giv…

Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended for this problem to be spe…

题目如下: Given a string S, check if the letters can be rearranged so that two characters that are adjacent to each other are not the same. If possible, output any possible result. If not possible, return the empty string. Example 1: Input: S = "aab"…

题目如下: Given two integers A and B, return any string S such that: S has length A + B and contains exactly A'a' letters, and exactly B 'b' letters; The substring 'aaa' does not occur in S; The substring 'bbb' does not occur in S. Example 1: Input: 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 使用额外空间 不使用额外空间 日期 题目地址:https://leetcode.com/problems/string-compression/description/ 题目描述 Given an array of characters, compress it in-place. The length after compression must…

Algorithm [leetcode]557. Reverse Words in a String III https://leetcode.com/problems/reverse-words-in-a-string-iii/ 1)problem Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace…

[leetcode]438. Find All Anagrams in a String Given a string s and a non-empty string p, find all the start indices of p's anagrams in s. Strings consists of lowercase English letters only and the length of both strings s and p will not be larger than…

[LeetCode]481. Magical String 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.cn/ 题目地址:https://leetcode.com/problems/magical-string/description/ 题目描述: A magical string S consists of only '1' and '2' and obeys the f…

[LeetCode]880. Decoded String at Index 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.cn/ 题目地址:https://leetcode.com/problems/decoded-string-at-index/description/ 题目描述: An encoded string S is given. To find and wri…

[LeetCode]833. Find And Replace in String 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.cn/ 题目地址:https://leetcode.com/problems/find-and-replace-in-string/description/ 题目描述: To some string S, we will perform some…

[LeetCode]678. Valid Parenthesis String 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/valid-parenthesis-string/description/ 题目描述: Given a string containing only three types…

[LeetCode]Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 递归和非递归,此提比较简单.广度优先遍历即可.关键之处就在于如何保持访问深度. 下面是4种代码: im…

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,…

Algorithm [leetcode]657. Robot Return to Origin https://leetcode.com/problems/robot-return-to-origin/ 1)problem There is a robot starting at position (0, 0), the origin, on a 2D plane. Given a sequence of its moves, judge if this robot ends up at (0,…

题目等级:Easy 题目描述: Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward. Example 1: Input: 121 Output: true Example 2: Input: -121 Output: false Explanation: From left to right, it reads -12…

链接:https://leetcode.com/tag/heap/ [23] Merge k Sorted Lists [215] Kth Largest Element in an Array (无序数组中最小/大的K个数)(2018年11月30日第一次复习) 给了一个无序数组,可能有重复数字,找到第 k 个最大的元素并且返回这个元素值. 题解:直接用直接用个堆保存数组中最大的 K 个数.时间复杂度是 O(NlogK). //时间复杂度是 O(NlogK), 用堆辅助. class Solut…

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…

[334]Increasing Triplet Subsequence (2019年2月14日,google tag)(greedy) 给了一个数组 nums,判断是否有三个数字组成子序列,使得子序列递增.题目要求time complexity: O(N),space complexity: O(1) Return true if there exists i, j, k such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k …

[1]Two Sum (2018年11月9日,k-sum专题,算法群衍生题) 给了一个数组 nums, 和一个 target 数字,要求返回一个下标的 pair, 使得这两个元素相加等于 target . 题解:我这次最大范围的优化代码, hash-table + one pass,时间复杂度 O(N),空间复杂度 O(N).重点在于动态找,一边生成hash-table的同时去找答案,不是先生成hash-table再开始找答案. //这种类似 hash 的能用 unordered_map 就不要…

[94]Binary Tree Inorder Traversal [95]Unique Binary Search Trees II (2018年11月14日,算法群) 给了一个 n,返回结点是 1 - n 的所有形态的BST. 题解:枚举每个根节点 r, 然后递归的生成左右子树的所有集合,然后做笛卡尔积. /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * Tr…

[3]Longest Substring Without Repeating Characters [11]Container With Most Water [15]3Sum (2019年2月26日) 给了一个乱序的数组,返回一个结果数组,数组里面每个元素是一个三元组, 三元组的和加起来为0. 题解:先固定第一个数,然后后面两个数的控制用夹逼定理,2 pointers 来解. class Solution { public: vector<vector<int>> threeSu…