http://acm.hust.edu.cn/vjudge/contest/view.action?cid=35800#problem/D
1 #include <iostream> 2 #include <algorithm> 3 #include <cstring> 4 #include <string> 5 #include <cstdio> 6 #include <vector> 7 #include <map> 8 using namespace std; 9 const int INF=1<<28; 10 const int N= 32; 11 12 bool vis[N]; 13 vector<int>p[N]; 14 map<string,int>name_id; 15 map<string,int>pos_id; 16 int value[N],link[N][N],ans; 17 18 int res() 19 { 20 int ans1 = 0; 21 for (int i = 1; i <= 23; i++) 22 if(vis[i]) 23 ans1+=value[i]; 24 for (int i = 1; i <= 23; i++) 25 { 26 for (int j = i+1; j <= 23; j++) 27 { 28 if (vis[i]&&vis[j]) 29 ans1+= link[i][j]; 30 } 31 } 32 return ans1; 33 } 34 35 void dfs4(int cnt,int pos) 36 { 37 if (cnt==4) 38 { 39 //cout<<res()<<endl; 40 ans = max(ans,res()); 41 return ; 42 } 43 for (int i = pos; i <(signed)p[4].size(); i++) 44 { 45 vis[p[4][i]] = true; 46 dfs4(cnt+1,i+1); 47 vis[p[4][i]] = false; 48 } 49 } 50 void dfs3(int cnt,int pos) 51 { 52 if (cnt==4) 53 { 54 dfs4(0,0); 55 return ; 56 } 57 for (int i = pos; i <(signed)p[3].size(); i++) 58 { 59 vis[p[3][i]] = true; 60 dfs3(cnt+1,i+1); 61 vis[p[3][i]] = false; 62 } 63 } 64 void dfs2(int cnt,int pos) 65 { 66 if (cnt==2) 67 { 68 dfs3(0,0); 69 return ; 70 } 71 for (int i = pos; i < (signed)p[2].size(); i++) 72 { 73 vis[p[2][i]] = true; 74 dfs2(cnt+1,i+1); 75 vis[p[2][i]] = false; 76 } 77 } 78 void dfs1(int cnt,int pos) 79 { 80 if (cnt==1) 81 { 82 dfs2(0,0); 83 return; 84 } 85 for (int i = pos; i < (signed)p[1].size(); i++) 86 { 87 vis[p[1][i]] = true; 88 dfs1(cnt+1,i+1); 89 vis[p[1][i]] = false; 90 } 91 } 92 void init() 93 { 94 ans = -INF; 95 name_id.clear(); 96 memset(value,0,sizeof(value)); 97 memset(link,0,sizeof(link)); 98 memset(vis,false,sizeof(vis)); 99 for (int i = 1; i <= 4; i++) 100 p[i].clear(); 101 } 102 int main() 103 { 104 pos_id["goalkeeper"] = 1; 105 pos_id["striker"] = 2; 106 pos_id["midfielder"] = 3; 107 pos_id["defender"] = 4; 108 string name,pos; 109 while(cin>>name) 110 { 111 init(); 112 cin>>value[1]>>pos; 113 name_id[name] = 1; 114 p[pos_id[pos]].push_back(1); 115 for (int i = 2; i <= 23; i++) 116 { 117 cin>>name>>value[i]>>pos; 118 name_id[name] = i; 119 p[pos_id[pos]].push_back(i); 120 } 121 int m,val; 122 string name1,name2; 123 cin>>m; 124 while(m--) 125 { 126 cin>>name1>>name2>>val; 127 link[name_id[name1]][name_id[name2]] = val; 128 link[name_id[name2]][name_id[name1]] = val; 129 } 130 if (p[1].size() < 1||p[2].size() < 2||p[3].size() < 4||p[4].size() < 4) 131 { 132 printf("impossible "); 133 continue; 134 } 135 dfs1(0,0); 136 printf("%d ",ans); 137 } 138 return 0; 139 }