{ "data": { "question": { "questionId": "264", "questionFrontendId": "264", "boundTopicId": null, "title": "Ugly Number II", "titleSlug": "ugly-number-ii", "content": "

An ugly number is a positive integer whose prime factors are limited to 2, 3, and 5.

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Given an integer n, return the nth ugly number.

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Example 1:

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\nInput: n = 10\nOutput: 12\nExplanation: [1, 2, 3, 4, 5, 6, 8, 9, 10, 12] is the sequence of the first 10 ugly numbers.\n
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Example 2:

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\nInput: n = 1\nOutput: 1\nExplanation: 1 has no prime factors, therefore all of its prime factors are limited to 2, 3, and 5.\n
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Constraints:

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