题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1301
#include<iostream>
#include<cstdio>
#include<cstring>
#define inf 0x3f3f3f3f
using namespace std;
int map[27][27],dis[27];
int n;
int Prim() {
int minn,ans=0;
dis[0]=0;
for(int i=1; i<n; i++)
dis[i]=map[0][i];
for(int i=1; i<n; i++) {//n-1次循环!!!!(卡的我、、、、)
int j,k;
minn=inf;
for(j=0; j<n; j++) {
if(dis[j]!=0&&dis[j]<minn) {
minn=dis[j];
k=j;
}
}
ans+=minn;
for(int j=0; j<n; j++)
dis[j]=min(dis[j],map[k][j]);
}
return ans;
}
int main() {
char ch,st;
int m,num;
while(~scanf("%d",&n)&&n) {
memset(map,inf,sizeof(map));
for(int i=0;i<n;i++)
map[i][i]=0;
int t=n-1;
while(t--) {
getchar();
scanf("%c%d",&st,&m);
for(int i=0; i<m; i++) {
getchar();
scanf("%c%d",&ch,&num);
map[st-'A'][ch-'A']=map[ch-'A'][st-'A']=num;
}
}
printf("%d\n",Prim());
}
}