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🔥Longest Palindromic Substring: Dynamic Symmetry ExpansionMedium
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Longest Palindromic Substring: Dynamic Symmetry Expansion

Targeted in FAANG & Tech OA:AmazonMicrosoftGoogle
Real-World Engineering Context
Used in genomic palindrome sequence identification, DNA restriction enzyme recognition sites, and reversible pattern compression.
Given a string `s`, return the longest palindromic substring in `s`.

Sample Test Cases

Input: ["babad"]
Expected: "bab"
Input: ["cbbd"]
Expected: "bb"
Input: ["a"]
Expected: "a"

Constraints

  • 1 <= s.length <= 1000
  • s consist of only digits and English letters.
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