{ "data": { "question": { "questionId": "2444", "questionFrontendId": "2370", "boundTopicId": null, "title": "Longest Ideal Subsequence", "titleSlug": "longest-ideal-subsequence", "content": "

You are given a string s consisting of lowercase letters and an integer k. We call a string t ideal if the following conditions are satisfied:

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Return the length of the longest ideal string.

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A subsequence is a string that can be derived from another string by deleting some or no characters without changing the order of the remaining characters.

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Note that the alphabet order is not cyclic. For example, the absolute difference in the alphabet order of 'a' and 'z' is 25, not 1.

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Example 1:

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\nInput: s = "acfgbd", k = 2\nOutput: 4\nExplanation: The longest ideal string is "acbd". The length of this string is 4, so 4 is returned.\nNote that "acfgbd" is not ideal because 'c' and 'f' have a difference of 3 in alphabet order.
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Example 2:

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\nInput: s = "abcd", k = 3\nOutput: 4\nExplanation: The longest ideal string is "abcd". The length of this string is 4, so 4 is returned.\n
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Constraints:

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