Valid Palindrome Checker

Given a string s, determine whether it is a palindrome by considering only alphanumeric characters and ignoring cases. In other words, after removing all non-alphanumeric characters and converting all letters to the same case, the string should read the same forwards and backwards.

A string s is a valid palindrome if it satisfies:

\( s = s_{\text{rev}} \)

where \( s_{\text{rev}} \) denotes the reversed string after filtering out non-alphanumeric characters. Note that an empty string is considered a valid palindrome.

inputFormat

The input consists of a single line containing a string s. The string may contain spaces, punctuation, or other non-alphanumeric characters.

outputFormat

Output True if the filtered string is a palindrome; otherwise, output False.

A man, a plan, a canal: Panama

True