Valid Parentheses

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. An input string is valid if brackets are closed in the correct order. Implement a function is_valid_parentheses(s: str) -> bool to verify, and consider optimizations and runtime. The input limit is up to 10^4. Provide complete test cases. Example Input ()