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Md Ariful Haque @mah-shamim

Minimum Add To Make Parentheses Valid In 60 Characters

Minimum moves to make parentheses valid: count unmatched '(' and ')' then add min of those two values.

921. Minimum Add to Make Parentheses Valid
Difficulty: Medium
Topics: String, Stack, Greedy
A parentheses string is valid if and only if:

It is the empty string,
It can be written as AB (A concatenated with B), where A and B are valid strings, or
It can be written as (A), where A is a valid string.

You are given a parentheses string s. In one move, you can insert a parenthesis at any position of the string.

For example, if s = "()))", you can insert an opening parenthesis to be "(()))" or a closing parenthesis to be "())))".

Return the minimum number of moves required to make s valid.
Exam...