hdu 1301(最小生成树kruskal)

/*
  Name: 最小生成树(kruskal) 
  Author: Try_86
  Date: 10/04/12 19:51
*/

#include <cstdio>
#include <cstdlib>
#include <iostream>

using namespace std;

const int M = 700;

int p[27], sum;
struct edge {
    int a;
    int b;
    int w;
}e[M];

int cmp(const void *a, const void *b) {
    return (*(edge *)a).w - (*(edge *)b).w;
}

void init(int vs) {
    for (int i=1; i<=vs; ++i) p[i] = i;
    return ;
}

int find(int v) {
    if (p[v] != v) p[v] = find(p[v]);
    return p[v];
}

int join(edge e) {
    int x, y;
    x = find(e.a);
    y = find(e.b);
    if (x != y) {
        ++sum;
        p[x] = y;
        return e.w;
    }
    return 0;
}

int kruskal(int es, int vs) {
    int ans = 0;
    init(vs);
    qsort(e, es, sizeof(edge), cmp);
    for (int i=0; i<es; ++i) {
        ans += join(e[i]);
        if (sum == vs) return ans;
    }
}

int main() {
    int n;
    while (cin>>n) {
        if (n == 0) break;
        char c;
        int k, w, es;
        es = 0;
        for (int i=1; i<n; ++i) {
            cin>>c>>k;
            for (int j=0; j<k; ++j) {
                cin>>c>>w;
                e[es].w = w;
                e[es].a = i;
                e[es].b = c - 'A' + 1;
                ++es;
            }
        }
        sum = 1;
        int ans = kruskal(es, n);
        printf ("%d\n", ans);
    }
    return 0;
}