Arranging Your Team

http://acm.hust.edu.cn/vjudge/contest/view.action?cid=35800#problem/D

 #include <iostream>
 #include <algorithm>
 #include <cstring>
 #include <string>
 #include <cstdio>
 #include <vector>
 #include <map>
 using namespace std;
 const int INF=<<;
 const int N= ;

 bool vis[N];
 vector<int>p[N];
 map<string,int>name_id;
 map<string,int>pos_id;
 int value[N],link[N][N],ans;

 int res()
 {
     int ans1 = ;
     for (int i = ; i <= ; i++)
         if(vis[i])
             ans1+=value[i];
     for (int i = ; i <= ; i++)
     {
         for (int j = i+; j <= ; j++)
         {
             if (vis[i]&&vis[j])
                 ans1+= link[i][j];
         }
     }
     return ans1;
 }

 void dfs4(int cnt,int pos)
 {
     if (cnt==)
     {
         //cout<<res()<<endl;
         ans = max(ans,res());
         return ;
     }
     for (int i = pos; i <(signed)p[].size(); i++)
     {
         vis[p[][i]] = true;
         dfs4(cnt+,i+);
         vis[p[][i]] = false;
     }
 }
 void dfs3(int cnt,int pos)
 {
     if (cnt==)
     {
         dfs4(,);
         return ;
     }
     for (int i = pos; i <(signed)p[].size(); i++)
     {
         vis[p[][i]] = true;
         dfs3(cnt+,i+);
         vis[p[][i]] = false;
     }
 }
 void dfs2(int cnt,int pos)
 {
     if (cnt==)
     {
         dfs3(,);
         return ;
     }
     for (int i = pos; i < (signed)p[].size(); i++)
     {
         vis[p[][i]] = true;
         dfs2(cnt+,i+);
         vis[p[][i]] = false;
     }
 }
 void dfs1(int cnt,int pos)
 {
     if (cnt==)
     {
         dfs2(,);
         return;
     }
     for (int i = pos; i < (signed)p[].size(); i++)
     {
         vis[p[][i]] = true;
         dfs1(cnt+,i+);
         vis[p[][i]] = false;
     }
 }
 void init()
 {
     ans = -INF;
     name_id.clear();
     memset(value,,sizeof(value));
     memset(link,,sizeof(link));
     memset(vis,false,sizeof(vis));
     for (int i = ; i <= ; i++)
         p[i].clear();
 }
 int main()
 {
     pos_id["goalkeeper"] = ;
     pos_id["striker"] = ;
     pos_id["midfielder"] = ;
     pos_id["defender"] = ;
     string name,pos;
     while(cin>>name)
     {
         init();
         cin>>value[]>>pos;
         name_id[name] = ;
         p[pos_id[pos]].push_back();
         for (int i = ; i <= ; i++)
         {
             cin>>name>>value[i]>>pos;
             name_id[name] = i;
             p[pos_id[pos]].push_back(i);
         }
         int m,val;
         string name1,name2;
         cin>>m;
         while(m--)
         {
             cin>>name1>>name2>>val;
             link[name_id[name1]][name_id[name2]] = val;
             link[name_id[name2]][name_id[name1]] = val;
         }
         if (p[].size() < ||p[].size() < ||p[].size() < ||p[].size() < )
         {
             printf("impossible\n");
             continue;
         }
         dfs1(,);
         printf("%d\n",ans);
     }
     return ;
 }