题解
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#define M 340
using namespace std;struct abcd
{int limit1,limit2,reward,length;friend bool operator < (const abcd &x,const abcd &y){if(x.reward>=0 && y.reward<0)return true;if(x.reward<0 && y.reward>=0)return false;if(x.reward>=0 && y.reward>=0)return x.limit1<y.limit1;return x.limit2>y.limit2;}
}a[M];int n,sum;
int f[M*M];
int main()
{char s[M];memset(f,0xef,sizeof f);f[0]=0;cin>>n;for(int i=1;i<=n;i++){int x=0,y=0;scanf("%s",s);for(int j=0;s[j];j++){if(s[j]=='(')y++;elsey?y--:x++;}a[i].limit1=x;a[i].limit2=y;a[i].reward=y-x;a[i].length=strlen(s);sum+=y;}sort(a+1,a+n+1);//for(int i=1;i<=n;i++)
// cout<<a[i].limit1<<' '<<a[i].limit2<<' '<<a[i].reward<<' '<<a[i].length<<endl;for(int i=1;i<=n;i++){if(a[i].reward<0)for(int j=a[i].limit1;j<=sum;j++)f[j+a[i].reward]=max(f[j+a[i].reward],f[j]+a[i].length);elsefor(int j=sum;j>=a[i].limit1;j--)f[j+a[i].reward]=max(f[j+a[i].reward],f[j]+a[i].length);}cout<<f[0]<<endl;return 0;
}