2116. Check if a Parentheses String Can Be Valid

A parentheses string is a non-empty string consisting only of '(' and ')'. It is valid if any of the following conditions is true: - It is (). - It can be written as AB (A concatenated with B), where A and B are valid parentheses strings. - It can be written as (A), where A is a valid parentheses string. You are given a parentheses string s and a string locked, both of length n. locked is a bi