题目如下: 解题思路:DFS或者BFS都行.本题的关键在于减少重复计算.我采用了两种方法:一是用字典dic_ladderlist记录每一个单词可以ladder的单词列表:另外是用dp数组记录从startword开始到wordlist每一个word的最小转换次数,这一点非常重要,可以过滤很多无效的运算. 代码如下: class Solution(object): def getLadderList(self, w,d): l = [] r = [] for i in xrange(26): l.a…

Word Ladder Given two words (start and end), and a dictionary, find the length of shortest transformation sequence from start to end, such that: Only one letter can be changed at a time Each intermediate word must exist in the dictionary For example,…

Word Break II Given a string s and a dictionary of words dict, add spaces in s to construct a sentence where each word is a valid dictionary word. Return all such possible sentences. For example, given s = "catsanddog", dict = ["cat",…

原题地址: https://oj.leetcode.com/submissions/detail/19446353/ 题目内容: Given two words (start and end), and a dictionary, find all shortest transformation sequence(s) from start to end, such that: Only one letter can be changed at a time Each intermediate…

Given an m x n board of characters and a list of strings words, return all words on the board. Each word must be constructed from letters of sequentially adjacent cells, where adjacent cells are horizontally or vertically neighboring. The same letter…

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 前缀树 日期 题目地址:https://leetcode.com/problems/word-search-ii/ 题目描述 Given a 2D board and a list of words from the dictionary, find all words in the board. Each word must be construc…

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 递归求解 日期 题目地址:https://leetcode.com/problems/word-break-ii/ 题目描述 Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, add spaces in s to con…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址: https://leetcode.com/problems/word-ladder/description/ 题目描述: Given two words (beginWord and endWord), and a dictionary's word list, find the length of shortest transformation sequence from…

127. Word Ladder 这道题使用bfs来解决,每次将满足要求的变换单词加入队列中. wordSet用来记录当前词典中的单词,做一个单词变换生成一个新单词,都需要判断这个单词是否在词典中,不在词典中就不能加入队列. pathCnt用来记录遍历到的某一个词使用的次数,做一个单词变换生成一个新单词,都需要判断这个单词是否在pathCnt中,如果在,则说明之前已经达到过,这次不用再计算了,因为这次计算的path肯定比之前多.pathCnt相当于剪枝. class Solution { pub…

126. Word Ladder II 题目 Given two words (beginWord and endWord), and a dictionary's word list, find all shortest transformation sequence(s) from beginWord to endWord, such that: Only one letter can be changed at a time Each transformed word must exist…