You are given a single line of text. Keep only its alphanumeric characters (letters and digits), treat uppercase and lowercase letters as equal, and ignore everything else (spaces, punctuation).
Decide whether the resulting sequence of characters reads the same left-to-right as right-to-left.
Input format
One line: a string s (it may contain letters, digits, spaces and punctuation; it may be empty).
Output format
Print YES if the cleaned string is a palindrome, otherwise NO. An empty cleaned string counts as a palindrome.
Constraints
- 0 <= len(s) <= 100000
scontains printable ASCII characters.