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

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

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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.

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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.

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

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Example 1:

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\nInput: words = ["a","b","ba","bca","bda","bdca"]\nOutput: 4\nExplanation: One of the longest word chains is ["a","ba","bda","bdca"].\n
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Example 2:

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\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
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Example 3:

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\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
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Constraints:

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C# 10 with .NET 6 runtime

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