hdu 6299 Balanced Sequence( 2018 Multi-University Training Contest 1 )

#include <stdio.h>
#include <iostream>
#include <cstdlib>
#include <cmath>
#include <string>
#include <cstring>
#include <algorithm>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <vector>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;

#define Faster ios::sync_with_stdio(false),cin.tie(0)
#define Read freopen("in.txt", "r", stdin),freopen("out.txt", "w", stdout)
const int INF = 0x3f3f3f3f;
const int maxn = 1e5 + 5;
const int MOD = 1e9 + 7;

struct node{
    int left, right;
    bool operator < (const node& x) const {
        if(left <= right && x.right < x.left) return false;
        else if(left > right && x.right >= x.left) return true;
        if(left <= right && x.right >= x.left) return left > x.left;
        else return right < x.right;
    }
}a[maxn];

int main() 
{
    Faster;
    int t;
    cin >> t;
    while(t--){
        int n;
        cin >> n;
        int ans = 0;
        for(int i = 0;i < n;i++){
            string s;
            cin >> s;
            a[i].left = a[i].right = 0;
            for(int j = 0;j < s.size();j++){
                if(s[j] == '('){
                    a[i].left++;
                }
                else if(s[j] == ')'){
                    if(a[i].left > 0){
                        a[i].left--;
                        ans += 2;
                    }
                    else{
                        a[i].right++;
                    }
                }
            }
        }
        sort(a, a+n);
        int now = 0;    //记录有多少左括号没有匹配
        for(int i = 0;i < n;i++){
            if(a[i].right > now)
                a[i].right = now;
            ans += a[i].right*2;
            now -= a[i].right;
            now += a[i].left;
        }
        cout << ans << endl;
    }    
    return 0;
}