A - Jungle Roads

A - Jungle Roads

思路：并查集的板子，重点是字符的转换，不能忘了加上1。

#include<cmath>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
int n;
int fa[27];
struct prog{
     int x,y,z;
}v[80];
bool cmp( prog a , prog b){
     return a.z<b.z;
}
int find(int x){
     return x==fa[x]?x:fa[x]=find(fa[x]);
}
int main(){
    while (scanf("%d",&n)&&n){
        for(int i=1;i<=27;i++)    fa[i]=i;
        int k=1;
        for(int i=1;i<=n-1;i++){
            char str[3];int m;
            cin>>str>>m;
            for(int j=1;j<=m;j++,k++){
                char str2[3];int t;
                cin>>str2>>t ;
                v[k].x=(str[0]-'A'+1);
                v[k].y=(str2[0]-'A'+1);
                v[k].z=t;
            }
        }
        sort(v+1,v+1+k,cmp);
        int ans=0;
        for(int i=1;i<=k;i++){
            int dx=find(v[i].x);
            int dy=find(v[i].y);
            if(dx==dy)    continue;
            ans+=v[i].z;
            fa[dx]=dy;
        }
        cout<<ans<<endl;
    }
    return 0;
}