Determine if the input string is a palindrome (reads the same forwards and backwards), ignoring case and non-alphanumeric characters.
Examples:
Input: str = "A man, a plan, a canal: Panama"
Output: true
Explanation: After removing non-alphanumeric characters and converting to lowercase, "amanaplanacanalpanama" reads the same forwards and backwards.
Input: str = "race a car"
Output: false
Explanation: After cleaning, "raceacar" is not a palindrome.
Apex Code Editor
Welcome to Lightning Challenge!
How It Works
- • Write your solution in the code editor
- • Connect your Salesforce org to test
- • Submit to check if your solution passes
- • Use hints if you get stuck
Contest Alert
🏆 #CodeEveryDay July 2026
Contest runs July 1 - 31. Complete challenges to climb the leaderboard!
Only the 31 daily challenges shown during this contest count toward points. Earlier dailies don't carry over.