leetcode 解题思路

You are asked to design a file systemthat allows you to create new paths and associate them with different values.The format of a path isone or more concatenated strings of the form:/followed by one or more lowercase English letters. For example, "/l...

Given a list of stringsdictwhere all the strings are of the same length.Returntrueif there are 2 strings that only differ by 1 character in the same index, otherwise returnfalse.Example 1:Input: dict = ["abcd","acbd", "aacd"]Output: trueExp...

Implement theStreamCheckerclass as follows:StreamChecker(words): Constructor, init the data structure with the given words. query(letter): returns true if and only if for somek >= 1, the lastkcharacters queried (in order from oldest to newest, i...

Implement a magic directory withbuildDict, andsearchmethods.For the methodbuildDict, you'll be given a list of non-repetitive words to build a dictionary.For the methodsearch, you'll be given a word, and judge whether if you modifyexactlyone cha...

Design a search autocomplete system for a search engine. Users may input a sentence (at least one word and end with a special character'#'). Foreach characterthey typeexcept '#', you need to retur...

Given an array of stringsproductsand a stringsearchWord. We want to design a system that suggests at most three product names fromproductsafter each character ofsearchWordis typed. Suggested pr...

Given a list of words (without duplicates), please write a program that returns all concatenated words in the given list of words.A concatenated word is defined as a string that is comprised entirel...

Given manywords,words[i]has weighti.Design a classWordFilterthat supports one function,WordFilter.f(String prefix, String suffix). It will return the word with givenprefixandsuffixwith ma...

Given a list of stringswordsrepresenting an English Dictionary, find the longest word inwordsthat can be built one character at a time by other words inwords. If there is more than one possible a...

trie字典树可以用来查找单词或者搜索剪枝用。Implement Trie (Prefix Tree)实现一个 Trie，包含insert,search, 和startsWith这三个方法。思路：模板必须记住；没有儿子建立儿子，有儿子走儿子；public class Trie { private class TrieNode { Trie...

Given a set of wordswithout duplicates, find allword squaresyou can build from them.A sequence of words forms a valid word square if the kth row and column read the exact same string, where 0 ≤ k...

Given a 2D board and a list of words from the dictionary, find all words in the board.Each word must be constructed from letters of sequentially adjacent cell, where "adjacent" cells are those horiz...

Given a set of strings which just has lower case letters and a target string, output all the strings for each the edit distance with the target no greater thank.You have the following 3 operations ...

Design a data structure that supports the following two operations:void addWord(word)bool search(word)search(word) can search a literal word or a regular expression string containing only le...

Given an array of words, find all shortest unique prefixes to represent each word in the given array. Assume that no word is prefix of another.Input: arr[] = {"zebra", "dog", "duck", "dove"}Output...

Implement a trie withinsert,search, andstartsWithmethods.Note:You may assume that all inputs are consist of lowercase lettersa-z.思路：首先建立一个TrieNode class，里面包含26个TireNode array，然后build trie...