Valid Palindrome Checker

Given a string s, determine whether it is a valid palindrome. A valid palindrome is defined as a string that reads the same forward and backward after removing all non-alphanumeric characters and converting all letters to the same case. For example, the string A man, a plan, a canal: Panama is a palindrome because after processing it becomes amanaplanacanalpanama.

Your task is to implement a program that reads a string from standard input and prints YES if the string is a valid palindrome, or NO otherwise.

Note: An empty string and a single-character string are considered palindromes.

inputFormat

The input consists of a single line containing the string s. The string can include spaces, punctuation, and other non-alphanumeric characters.

outputFormat

Output a single line: YES if the processed string is a palindrome, or NO otherwise.

A man, a plan, a canal: Panama

YES