{ "data": { "question": { "questionId": "1129", "questionFrontendId": "1048", "categoryTitle": "Algorithms", "boundTopicId": 5276, "title": "Longest String Chain", "titleSlug": "longest-string-chain", "content": "

You are given an array of words where each word consists of lowercase English letters.

\n\n

wordA is a predecessor of wordB if and only if we can insert exactly one letter anywhere in wordA without changing the order of the other characters to make it equal to wordB.

\n\n\n\n

A word chain is a sequence of words [word1, word2, ..., wordk] with k >= 1, where word1 is a predecessor of word2, word2 is a predecessor of word3, and so on. A single word is trivially a word chain with k == 1.

\n\n

Return the length of the longest possible word chain with words chosen from the given list of words.

\n\n

 

\n

Example 1:

\n\n
\nInput: words = ["a","b","ba","bca","bda","bdca"]\nOutput: 4\nExplanation: One of the longest word chains is ["a","ba","bda","bdca"].\n
\n\n

Example 2:

\n\n
\nInput: words = ["xbc","pcxbcf","xb","cxbc","pcxbc"]\nOutput: 5\nExplanation: All the words can be put in a word chain ["xb", "xbc", "cxbc", "pcxbc", "pcxbcf"].\n
\n\n

Example 3:

\n\n
\nInput: words = ["abcd","dbqca"]\nOutput: 1\nExplanation: The trivial word chain ["abcd"] is one of the longest word chains.\n["abcd","dbqca"] is not a valid word chain because the ordering of the letters is changed.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "最长字符串链", "translatedContent": "

给出一个单词数组 words ，其中每个单词都由小写英文字母组成。

\n\n

如果我们可以 不改变其他字符的顺序 ，在 wordA 的任何地方添加 恰好一个 字母使其变成 wordB ，那么我们认为 wordA 是 wordB 的 前身 。

\n\n\n\n

词链是单词 [word_1, word_2, ..., word_k] 组成的序列，k >= 1，其中 word1 是 word2 的前身，word2 是 word3 的前身，依此类推。一个单词通常是 k == 1 的 单词链 。

\n\n

从给定单词列表 words 中选择单词组成词链，返回 词链的 最长可能长度 。
\n 

\n\n

示例 1：

\n\n
\n输入：words = [\"a\",\"b\",\"ba\",\"bca\",\"bda\",\"bdca\"]\n输出：4\n解释：最长单词链之一为 [\"a\",\"ba\",\"bda\",\"bdca\"]\n
\n\n

示例 2:

\n\n
\n输入：words = [\"xbc\",\"pcxbcf\",\"xb\",\"cxbc\",\"pcxbc\"]\n输出：5\n解释：所有的单词都可以放入单词链 [\"xb\", \"xbc\", \"cxbc\", \"pcxbc\", \"pcxbcf\"].\n
\n\n

示例 3:

\n\n
\n输入：words = [\"abcd\",\"dbqca\"]\n输出：1\n解释：字链[\"abcd\"]是最长的字链之一。\n[\"abcd\"，\"dbqca\"]不是一个有效的单词链，因为字母的顺序被改变了。\n
\n\n

 

\n\n

提示：

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"CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class Solution {\n public int LongestStrChain(string[] words) {\n\n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\n * @param {string[]} words\n * @return {number}\n */\nvar longestStrChain = function(words) {\n\n};", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "# @param {String[]} words\n# @return {Integer}\ndef longest_str_chain(words)\n\nend", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "class Solution {\n func longestStrChain(_ words: [String]) -> Int {\n\n }\n}", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "func longestStrChain(words []string) int {\n\n}", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "object Solution {\n def longestStrChain(words: Array[String]): Int = {\n\n }\n}", "__typename": 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