Determine if a string is a palindrome, ignoring non-alphanumeric characters and case.

Examples

Example 1

Input:  "A man, a plan, a canal: Panama"
Output: true

"amanaplanacanalpanama" reads the same forwards and backwards

Example 2

Input:  "race a car"
Output: false

Constraints

• Ignore punctuation and spaces
• Case-insensitive