07 2020 档案

159. Longest Substring with At Most Two Distinct Characters 159.最长两个不同字符的子字符串
摘要：Given a string s , find the length of the longest substring t that contains at most 2 distinct characters. Example 1: Input: "eceba" Output: 3 Explana 阅读全文
posted @ 2020-07-31 23:22 苗妙苗 阅读(123) 评论(0) 推荐(0)
3. Longest Substring Without Repeating Characters 最长子串，无重复字符
摘要：Given a string, find the length of the longest substring without repeating characters. Example 1: Input: "abcabcbb" Output: 3 Explanation: The answer 阅读全文
posted @ 2020-07-31 11:19 苗妙苗 阅读(135) 评论(0) 推荐(0)
76. Minimum Window Substring 76.最小窗口子字符串BANC
摘要：Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n). Example: Input: S = "ADOB 阅读全文
posted @ 2020-07-30 10:34 苗妙苗 阅读(122) 评论(0) 推荐(0)
301. Remove Invalid Parentheses去除不符合匹配规则的括号
摘要：Remove the minimum number of invalid parentheses in order to make the input string valid. Return all possible results. Note: The input string may cont 阅读全文
posted @ 2020-07-28 11:02 苗妙苗 阅读(160) 评论(0) 推荐(0)
22. Generate Parentheses产生所有匹配括号的方案
摘要：Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses. For example, given n = 3, a solution set is: [ 阅读全文
posted @ 2020-07-27 23:16 苗妙苗 阅读(106) 评论(0) 推荐(0)
320. Generalized Abbreviation 单词缩写
摘要：Write a function to generate the generalized abbreviations of a word. Note: The order of the output does not matter. Example: Input: "word" Output: [" 阅读全文
posted @ 2020-07-27 11:17 苗妙苗 阅读(98) 评论(0) 推荐(0)
282. Expression Add Operators 加减乘的全部路径
摘要：Given a string that contains only digits 0-9 and a target value, return all possibilities to add binary operators (not unary) +, -, or * between the d 阅读全文
posted @ 2020-07-27 01:44 苗妙苗 阅读(162) 评论(0) 推荐(0)
494. Target Sum 494.目标总和
摘要：You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose o 阅读全文
posted @ 2020-07-25 11:16 苗妙苗 阅读(100) 评论(0) 推荐(0)
247. Strobogrammatic Number II 倒过来看也一样的数
摘要：A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Find all strobogrammatic numbers that are o 阅读全文
posted @ 2020-07-25 06:41 苗妙苗 阅读(102) 评论(0) 推荐(0)
93. Restore IP Addresses 93.恢复IP地址
摘要：Given a string containing only digits, restore it by returning all possible valid IP address combinations. A valid IP address consists of exactly four 阅读全文
posted @ 2020-07-23 20:38 苗妙苗 阅读(172) 评论(0) 推荐(0)
一般DFS和回溯法的区别
摘要：所谓优化剪枝策略，就是判断当前的分支树是否符合问题的条件，如果当前分支树不符合条件，那么就不再遍历这个分支里的所有路径。回溯算法使用剪枝函数，剪去一些不可能到达 最终状态（即答案状态）的节点，从而减少状态空间树节点的生成。 有个解空间，要从里面挑。有条件，不符合就剪枝：一般是数组长度够了就行了可是一 阅读全文
posted @ 2020-07-18 10:02 苗妙苗 阅读(2541) 评论(0) 推荐(0)
17. Letter Combinations of a Phone Number 17.电话号码的字母组合
摘要：Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could represent. A mapping of digit to le 阅读全文
posted @ 2020-07-18 08:18 苗妙苗 阅读(140) 评论(0) 推荐(0)
17. Letter Combinations of a Phone Number 17.电话号码的字母组合
摘要：Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could represent. A mapping of digit to le 阅读全文
posted @ 2020-07-10 09:34 苗妙苗 阅读(161) 评论(0) 推荐(0)
79. Word Search DFS矩阵中搜索单词
摘要：Given a 2D board and a word, find if the word exists in the grid. The word can be constructed from letters of sequentially adjacent cell, where "adjac 阅读全文
posted @ 2020-07-07 23:01 苗妙苗 阅读(207) 评论(0) 推荐(0)
200. Number of Islands 200.岛屿数（可以形状一样）
摘要：Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacen 阅读全文
posted @ 2020-07-06 22:13 苗妙苗 阅读(161) 评论(0) 推荐(0)
694. Number of Distinct Islands 694.独立岛屿数
摘要：Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) Yo 阅读全文
posted @ 2020-07-06 11:01 苗妙苗 阅读(108) 评论(0) 推荐(0)
695. Max Area of Island最大岛屿面积
摘要：Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) Yo 阅读全文
posted @ 2020-07-04 22:39 苗妙苗 阅读(128) 评论(0) 推荐(0)
491. Increasing Subsequences 491.增加子序列
摘要：Given an integer array, your task is to find all the different possible increasing subsequences of the given array, and the length of an increasing su 阅读全文
posted @ 2020-07-03 05:51 苗妙苗 阅读(138) 评论(0) 推荐(0)
131. Palindrome Partitioning 131.回文分区
摘要：Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s. Example: I 阅读全文
posted @ 2020-07-01 23:28 苗妙苗 阅读(113) 评论(0) 推荐(0)
40. Combination Sum II 凑一个和，不能重复用一个元素
摘要：Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in candidates where the candidate numb 阅读全文
posted @ 2020-07-01 08:11 苗妙苗 阅读(112) 评论(0) 推荐(0)
40. Combination Sum II 凑出一个和，不可以重复用元素（含duplicates）
摘要：Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in candidates where the candidate numb 阅读全文
posted @ 2020-07-01 05:37 苗妙苗 阅读(99) 评论(0) 推荐(0)
39. Combination Sum 凑出一个和，可以重复用元素（含duplicates）
摘要：Given a set of candidate numbers (candidates) (without duplicates) and a target number (target), find all unique combinations in candidates where the 阅读全文
posted @ 2020-07-01 05:22 苗妙苗 阅读(155) 评论(0) 推荐(0)