{ "data": { "question": { "questionId": "2130", "questionFrontendId": "2002", "boundTopicId": null, "title": "Maximum Product of the Length of Two Palindromic Subsequences", "titleSlug": "maximum-product-of-the-length-of-two-palindromic-subsequences", "content": "

Given a string s, find two disjoint palindromic subsequences of s such that the product of their lengths is maximized. The two subsequences are disjoint if they do not both pick a character at the same index.

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Return the maximum possible product of the lengths of the two palindromic subsequences.

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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. A string is palindromic if it reads the same forward and backward.

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Example 1:

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\nInput: s = "leetcodecom"\nOutput: 9\nExplanation: An optimal solution is to choose "ete" for the 1st subsequence and "cdc" for the 2nd subsequence.\nThe product of their lengths is: 3 * 3 = 9.\n
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Example 2:

\n\n
\nInput: s = "bb"\nOutput: 1\nExplanation: An optimal solution is to choose "b" (the first character) for the 1st subsequence and "b" (the second character) for the 2nd subsequence.\nThe product of their lengths is: 1 * 1 = 1.\n
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Example 3:

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\nInput: s = "accbcaxxcxx"\nOutput: 25\nExplanation: An optimal solution is to choose "accca" for the 1st subsequence and "xxcxx" for the 2nd subsequence.\nThe product of their lengths is: 5 * 5 = 25.\n
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Constraints:

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