{ "data": { "question": { "questionId": "3584", "questionFrontendId": "3302", "boundTopicId": null, "title": "Find the Lexicographically Smallest Valid Sequence", "titleSlug": "find-the-lexicographically-smallest-valid-sequence", "content": "

You are given two strings word1 and word2.

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A string x is called almost equal to y if you can change at most one character in x to make it identical to y.

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A sequence of indices seq is called valid if:

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Return an array of size word2.length representing the lexicographically smallest valid sequence of indices. If no such sequence of indices exists, return an empty array.

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Note that the answer must represent the lexicographically smallest array, not the corresponding string formed by those indices.

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Example 1:

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Input: word1 = "vbcca", word2 = "abc"

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Output: [0,1,2]

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Explanation:

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The lexicographically smallest valid sequence of indices is [0, 1, 2]:

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Example 2:

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Input: word1 = "bacdc", word2 = "abc"

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Output: [1,2,4]

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Explanation:

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The lexicographically smallest valid sequence of indices is [1, 2, 4]:

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Example 3:

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Input: word1 = "aaaaaa", word2 = "aaabc"

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Output: []

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Explanation:

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There is no valid sequence of indices.

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Example 4:

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Input: word1 = "abc", word2 = "ab"

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Output: [0,1]

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Constraints:

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Most standard library headers are already included automatically for your convenience.

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Python 2.7.12.

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C# 12 with .NET 8 runtime

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Node.js 20.10.0.

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Ruby 3.2

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You may use swift-algorithms 1.2.0 and swift-collections 1.1.0.

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Go 1.23

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Kotlin 1.9.0.

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PHP 8.2.

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Racket CS v8.11

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