Tsinsen-A1491 家族【并查集】

 1 #include <bits/stdc++.h>
 2 #define rep(i, a, b) for (int i = a; i <= b; i++)
 3 #define drep(i, a, b) for (int i = a; i >= b; i--)
 4 #define REP(i, a, b) for (int i = a; i < b; i++)
 5 #define mp make_pair
 6 #define pb push_back
 7 #define clr(x) memset(x, 0, sizeof(x))
 8 #define xx first
 9 #define yy second
10 using namespace std;
11 typedef long long i64;
12 typedef pair<int, int> pii;
13 const int inf = ~0U >> 1;
14 const i64 INF = ~0ULL >> 1;
15 //********************************
16 const int maxn = 1005, maxm = 5005;
17 pair<int, pii> edge[maxm];
18 int val[maxn], father[maxn], sze[maxn];
19 inline int getfather(int x) { return father[x] == x ? x : father[x] = getfather(father[x]); }
20 int main() {
21     int n, m, k;
22     scanf("%d%d%d", &n, &m, &k);
23     rep(i, 1, n) scanf("%d", &val[i]);
24     rep(i, 1, m) scanf("%d%d%d", &edge[i].yy.xx, &edge[i].yy.yy, &edge[i].xx);
25     sort(edge + 1, edge + 1 + m);
26     int ret = inf;
27     rep(i, 1, m) {
28         rep(o, 1, n) sze[o] = 1, father[o] = o;
29         int ans = n * val[1];
30         rep(j, i, m) {
31             if (j != i && edge[j].xx != edge[j - 1].xx) {
32                 if (ans >= k) {
33                     ret = min(ret, edge[j - 1].xx - edge[i].xx);
34                     break;
35                 }
36             }
37             int fx = getfather(edge[j].yy.xx), fy = getfather(edge[j].yy.yy);
38             if (fx != fy) {
39                 father[fy] = fx;
40                 ans -= val[sze[fy]] + val[sze[fx]];
41                 sze[fx] += sze[fy];
42                 sze[fy] = 0;
43                 ans += val[sze[fx]];
44             }
45         }
46         if (ans >= k) ret = min(ret, edge[m].xx - edge[i].xx);
47     }
48     if (ret == inf) puts("T_T");
49     else printf("%d\n", ret);
50     return 0;
51 }