Valid Palindrome Checker

Given an input string, determine whether it is a valid palindrome. A string is considered a valid palindrome if, after converting all uppercase letters to lowercase and removing all non-alphanumeric characters, it reads the same forwards and backwards.

The checking should be performed after normalizing the string, i.e., converting to lowercase and filtering only alphanumeric characters.

Note: The input string may contain spaces, punctuation, and mixed case letters. An empty string or a string with only non-alphanumeric characters should be considered a valid palindrome.

inputFormat

The input consists of a single line containing a string s.

Input is read from stdin.

outputFormat

Print True if the normalized string is a palindrome, otherwise print False. The output should be written to stdout.

A man, a plan, a canal: Panama

True