{ "data": { "question": { "questionId": "1761", "questionFrontendId": "1641", "boundTopicId": null, "title": "Count Sorted Vowel Strings", "titleSlug": "count-sorted-vowel-strings", "content": "

Given an integer n, return the number of strings of length n that consist only of vowels (a, e, i, o, u) and are lexicographically sorted.

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A string s is lexicographically sorted if for all valid i, s[i] is the same as or comes before s[i+1] in the alphabet.

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Example 1:

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\nInput: n = 1\nOutput: 5\nExplanation: The 5 sorted strings that consist of vowels only are ["a","e","i","o","u"].\n
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Example 2:

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\nInput: n = 2\nOutput: 15\nExplanation: The 15 sorted strings that consist of vowels only are\n["aa","ae","ai","ao","au","ee","ei","eo","eu","ii","io","iu","oo","ou","uu"].\nNote that "ea" is not a valid string since 'e' comes after 'a' in the alphabet.\n
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Example 3:

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\nInput: n = 33\nOutput: 66045\n
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Constraints:

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