uva 10048 Audiophobia(最小生成树）

#include <stdio.h>
#include <string.h>
#include <algorithm>
using namespace std;
const int N = 105;
const int M = 1005;
const int Q = 10005;
struct state {
int r, l, num;
}s[M];
int n, m, f
;

int getfather(int x) {
return x == f[x] ? x : f[x] = getfather(f[x]);
}

bool cmp(const state& a, const state& b) {
return a.num < b.num;
}

void init() {
for (int i = 0; i < m; i++)
scanf("%d%d%d", &s[i].l, &s[i].r, &s[i].num);
sort(s, s + m, cmp);
}

int kruskal() {
int a, b;
scanf("%d%d", &a, &b);
for (int i = 1; i <= n; i++)
f[i] = i;
for (int i = 0; i < m; i++) {
int p = getfather(s[i].l), q = getfather(s[i].r);
if (p != q) {
f[p] = q;
if (getfather(a) == getfather(b))
return s[i].num;
}
}
return -1;
}

int main () {
int cas = 0, q;
while (scanf("%d%d%d", &n, &m, &q), n || m || q) {
init();
if (cas) printf("\n");
printf("Case #%d\n", ++cas);
for (int i = 0; i < q; i++) {
int ans = kruskal();
if (ans < 0)
printf("no path\n");
else
printf("%d\n", ans);
}
}
return 0;
}