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🔥Palindromic Substrings: Center Expansion CounterMedium
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Palindromic Substrings: Center Expansion Counter

Targeted in FAANG & Tech OA:GoogleMicrosoftMeta
Real-World Engineering Context
Used in bioinformatic palindrome hairpin loop RNA folding analysis and data compression algorithms.
Given a string `s`, return the number of palindromic substrings in it. A string is a palindrome when it reads the same backward as forward. A substring is a contiguous sequence of characters within the string.

Sample Test Cases

Input: ["abc"]
Expected: 3
Input: ["aaa"]
Expected: 6
Input: ["a"]
Expected: 1

Constraints

  • 1 <= s.length <= 1000
  • s consists of lowercase English letters.
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