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🔥Valid Palindrome: Clean String SymmetryEasy
DAILY PROBLEM OF THE DAY+50 XP • Daily Streak

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EasyTwo Pointers•Acceptance: 46.3%

Valid Palindrome: Clean String Symmetry

Targeted in FAANG & Tech OA:GoogleAmazonMicrosoftSwiggy
Real-World Engineering Context
DNA bioinformatics palindrome sequence matching and search query sanitization in Elasticsearch.
A phrase is a palindrome if, after converting all uppercase letters into lowercase letters and removing all non-alphanumeric characters, it reads the same forward and backward. Return `true` if it is a palindrome, or `false` otherwise.

Sample Test Cases

Input: ["A man, a plan, a canal: Panama"]
Expected: true
Input: ["race a car"]
Expected: false
Input: [" "]
Expected: true

Constraints

  • 1 <= s.length <= 2 * 10^5
  • s consists only of printable ASCII characters.
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