{ "data": { "question": { "questionId": "516", "questionFrontendId": "516", "boundTopicId": null, "title": "Longest Palindromic Subsequence", "titleSlug": "longest-palindromic-subsequence", "content": "

Given a string s, find the longest palindromic subsequence's length in s.

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

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Example 1:

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\nInput: s = "bbbab"\nOutput: 4\nExplanation: One possible longest palindromic subsequence is "bbbb".\n
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Example 2:

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\nInput: s = "cbbd"\nOutput: 2\nExplanation: One possible longest palindromic subsequence is "bb".\n
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Constraints:

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