最小生成树【模板】 

 1 #include <iostream> 
 2 #include <cstdio>
 3 #include <algorithm>
 4 #include <cmath>
 5 using namespace std;
 6 
 7 const int maxn = 500;
 8 
 9 int n, m;
10 int x[maxn], y[maxn], f[maxn];
11 int ans = 0;
12 
13 struct node {
14     int x, y;
15     int val;
16 }dis[50100];
17 
18 bool cmp(node a, node b) {
19     return a.val < b.val;
20 }
21 
22 int find(int x) {
23     int r = x;
24     while(r != f[r]) r = f[r];
25     int i = x, j;
26     while(f[i] != r) {  
27         j = f[i];  
28         f[i] = r;  
29         i = j;  
30     }
31     return r;  
32 }
33 
34 void merge(int x, int y) {
35     x = find(x);
36     y = find(y);
37     if(x != y) f[y] = x;
38 }
39 
40 int main() {
41     cin >> n >> m;
42     for(int i = 1; i <= m; i++) {
43         cin >> dis[i].x >> dis[i].y >> dis[i].val;
44     }
45     for(int i = 1; i <= n; i++) f[i] = i;
46 
47     sort(dis + 1, dis + m + 1, cmp);
48     int tmp = 0, maxn = 0;
49     for(int i = 1; i <= m; i++) {
50         if(find(dis[i].x) != find(dis[i].y)) {
51             merge(dis[i].x, dis[i].y);
52             tmp++;
53             maxn = max(maxn, dis[i].val);
54         }
55         if(tmp == n - 1) break;
56     }
57 
58     cout << tmp << ' ' << maxn;
59 }

 

posted @ 2018-05-04 10:43  MekakuCityActor  阅读(131)  评论(0)    收藏  举报