HDU 1301 Jungle Roads

 1 #include <iostream>
 2 #include <cstring>
 3 #include <cstdio>
 4 #include <algorithm>
 5 #include <cmath>
 6 using namespace std;
 7 
 8 const int INF = 99999999 ;
 9 const int maxn = 105 ;
10 
11 int map[maxn][maxn];
12 int visit[maxn];
13 int low[maxn];
14 
15 int main (){
16     int n;
17     while (~scanf ("%d",&n)&&n){
18         for (int i=0;i<n;i++)
19             for (int j=0;j<n;j++)
20                 map[i][j]=INF;
21         for (int i=0;i<n-1;i++){
22             char c[10];
23             int a,b;
24             scanf ("%s%d",c,&a);
25             while (a--){
26                 scanf ("%s%d",c,&b);
27                 map[i][(int)(c[0]-‘A‘)]=map[(int)(c[0]-‘A‘)][i]=b;
28             }//cout<<n<<" "<<i<<endl;
29         }
30         memset (visit,0,sizeof visit);
31         int ans=0;
32         int mi;
33         int pos=1;
34         visit[1]=1;
35         for (int i=0;i<n;i++)
36             low[i]=map[pos][i];
37         for (int i=0;i<n-1;i++){
38             mi=INF;
39             for (int j=0;j<n;j++)
40                 if (!visit[j]&&low[j]<mi){
41                     mi=low[j];pos=j;
42                 }
43             ans+=mi;visit[pos]=1;
44             for (int j=0;j<n;j++)
45                 if (!visit[j])
46                     low[j]=min (low[j],map[pos][j]);
47         }
48         printf ("%d\n",ans);
49     }
50     return 0;
51 }