A parentheses string is valid if and only if:
AB
(A
concatenated with B
), where A
and B
are valid strings, or(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.
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.
Example 1:
Input: s = "())" Output: 1
Example 2:
Input: s = "(((" Output: 3
Constraints:
1 <= s.length <= 1000
s[i]
is either '('
or ')'
.