A bracket sequence is a string containing only characters "(" and ")". A regular bracket sequence (or, shortly, an RBS) is a bracket sequence that can be transformed into a correct arithmetic expression by inserting characters "1" and "+" between the original characters of the sequence. For example:
Let's denote the concatenation of two strings $$$x$$$ and $$$y$$$ as $$$x+y$$$. For example, "()()" $$$+$$$ ")(" $$$=$$$ "()())(".
You are given $$$n$$$ bracket sequences $$$s_1, s_2, \dots, s_n$$$. You can rearrange them in any order (you can rearrange only the strings themselves, but not the characters in them).
Your task is to rearrange the strings in such a way that the string $$$s_1 + s_2 + \dots + s_n$$$ has as many non-empty prefixes that are RBS as possible.
The first line contains a single integer $$$n$$$ ($$$1 \le n \le 20$$$).
Then $$$n$$$ lines follow, the $$$i$$$-th of them contains $$$s_i$$$ — a bracket sequence (a string consisting of characters "(" and/or ")". All sequences $$$s_i$$$ are non-empty, their total length does not exceed $$$4 \cdot 10^5$$$.
Print one integer — the maximum number of non-empty prefixes that are RBS for the string $$$s_1 + s_2 + \dots + s_n$$$, if the strings $$$s_1, s_2, \dots, s_n$$$ can be rearranged arbitrarily.
2 ( )
1
4 ()()()) ( ( )
4
1 (())
1
1 )(()
0
In the first example, you can concatenate the strings as follows: "(" $$$+$$$ ")" $$$=$$$ "()", the resulting string will have one prefix, that is an RBS: "()".
In the second example, you can concatenate the strings as follows: "(" $$$+$$$ ")" $$$+$$$ "()()())" $$$+$$$ "(" $$$=$$$ "()()()())(", the resulting string will have four prefixes that are RBS: "()", "()()", "()()()", "()()()()".
The third and the fourth examples contain only one string each, so the order is fixed.
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