Palindrome Check With Complexity | Dataford Interview Questions

Decision Point's QA validation utilities need to identify whether an input string is a palindrome. Implement a function that compares the string case-insensitively while ignoring spaces, punctuation, and other non-alphanumeric characters.

Use a two-pointer approach so the function runs in linear time and uses constant auxiliary space. An empty string after normalization is considered a palindrome.

Formal Specification

Input: s, a string containing letters, digits, whitespace, and punctuation.
Output: Return True if the normalized string reads identically from left to right and right to left. Otherwise, return False.
Normalization: Keep only alphanumeric characters and compare them without regard to case.

Constraints

0 <= len(s) <= 10^5
s contains printable characters and Unicode alphanumeric characters
Comparison is case-insensitive
Non-alphanumeric characters are ignored
An empty normalized string is a palindrome

Function Signature

def is_palindrome(s):

Your question is Palindrome Check With Complexity. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem