CodeTON Round 3 (Div. 1 + Div. 2, Rated, Prizes!)
E
Bracket Cost
Codeforces
2400
原题
← DF →
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Daemon Targaryen decided to stop looking like a Metin2 character. He turned himself into the most beautiful thing, a bracket sequence.

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For a bracket sequence, we can do two kind of operations:

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  • Select one of its substrings$^\dagger$ and cyclic shift it to the right. For example, after a cyclic shift to the right, "(())" will become ")(()";
  • Insert any bracket, opening '(' or closing ')', wherever you want in the sequence.
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We define the cost of a bracket sequence as the minimum number of such operations to make it balanced$^\ddagger$.

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Given a bracket sequence $s$ of length $n$, find the sum of costs across all its $\frac{n(n+1)}{2}$ non-empty substrings. Note that for each substring we calculate the cost independently.

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$^\dagger$ A string $a$ is a substring of a string $b$ if $a$ can be obtained from $b$ by deletion of several (possibly, zero or all) characters from the beginning and several (possibly, zero or all) characters from the end.

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$^\ddagger$ A sequence of brackets is called balanced if one can turn it into a valid math expression by adding characters $+$ and $1$. For example, sequences "(())()", "()", and "(()(()))" are balanced, while ")(", "(()", and "(()))(" are not.

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Input

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Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \leq t \leq 10^5$) — the number of test cases. The description of test cases follows.

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The first line of each test case contains a single integer $n$ ($1 \le n \le 2 \cdot 10^5$) — the length of the bracket sequence.

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The second line of each test case contains a string $s$, consisting only of characters '(' and ')', of length $n$ — the bracket sequence.

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It is guaranteed that sum of $n$ across all test cases does not exceed $2 \cdot 10^5$.

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Output

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For each test case, print a single integer — the sum of costs of all substrings of $s$.

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Note

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In the first test case, there is the only substring ")". Its cost is $1$ because we can insert '(' to the beginning of this substring and get a string "()", that is a balanced string.

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In the second test case, the cost of each substring of length one is $1$. The cost of a substring ")(" is $1$ because we can cyclically shift it to right and get a string "()". The cost of strings ")()" and "()(" is $1$ because its enough to insert one bracket to each of them. The cost of substring ")()(" is $1$ because we can cyclically shift it to right and get a string "()()". So there are $4 + 2 + 2 + 1 = 9$ substring of cost $1$ and $1$ substring of cost $0$. So the sum of the costs is $9$.

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In the third test case,

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  • "(", the cost is $1$;
  • "()", the cost is $0$;
  • "())", the cost is $1$;
  • ")", the cost is $1$;
  • "))", the cost is $2$;
  • ")", the cost is $1$.
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So the sum of the costs is $6$.

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样例

Input #1
5
1
)
4
)()(
3
())
5
(((((
10
)(())))())
Output #1
1
9
6
35
112
InputCopy OutputCopy
题目信息
题号
1750E
时间限制
2 s
内存限制
256 MB
标签
二分
数据结构
分治
动态规划
贪心
字符串

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。