{ "data": { "question": { "questionId": "647", "questionFrontendId": "647", "boundTopicId": null, "title": "Palindromic Substrings", "titleSlug": "palindromic-substrings", "content": "

Given a string s, return the number of palindromic substrings in it.

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A string is a palindrome when it reads the same backward as forward.

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A substring is a contiguous sequence of characters within the string.

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Example 1:

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\nInput: s = "abc"\nOutput: 3\nExplanation: Three palindromic strings: "a", "b", "c".\n
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Example 2:

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\nInput: s = "aaa"\nOutput: 6\nExplanation: Six palindromic strings: "a", "a", "a", "aa", "aa", "aaa".\n
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Constraints:

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