Code RoomValid palindrome ignoring punctuation
EasyPrep Room Coding #1517

Valid palindrome ignoring punctuation

CodingAlgorithms & data structuresEntry–Mid~10 min

Given a string s, return True if it reads the same forwards and backwards considering only alphanumeric characters and ignoring case; otherwise return False. Non-alphanumeric characters (spaces, punctuation) are skipped entirely. An empty or all-punctuation string is considered a palindrome.

Implement
is_clean_palindrome(s: str) → bool
Examples
in["A man, a plan, a canal: Panama"]outtrue
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

0:00 of about 10 min
InputExpectedGot
["A man, a plan, a canal: Panama"]truenot run yetsample