hdu 1233 还是畅通工程（最小生成树）

 1 #include<iostream>
 2 #include<stdio.h>
 3 #include<string.h>
 4 #include<stdlib.h>
 5 #include<math.h>
 6 #include<algorithm>
 7 #define LL long long
 8 #define mod 1e9 + 7
 9 const int M = 105;
10 
11 using namespace std;
12 
13 struct node{
14     int x;
15     int y;
16     int value;
17 }a[M * M >> 1];
18 
19 int cun[M];
20 
21 
22 bool cmp(node a, node b)
23 {
24     return a.value < b.value;
25 }
26 
27 int find(int x)
28 {
29     return cun[x] == x ? x : cun[x] = find(cun[x]);
30 }
31 
32 void shu(int x, int y)
33 {
34     int p = find(x);
35     int q = find(y);
36     cun[p] = q;
37 }
38 
39 int main()
40 {
41     int n;
42     while( cin >> n , n )
43     {
44         int t = n * (n - 1) / 2;
45         for(int i = 0; i < t; ++i)
46             scanf("%d%d%d",&a[i].x,&a[i].y,&a[i].value);
47         for(int i = 0; i <= n; ++i)
48             cun[i] = i;
49         sort(a,a + t,cmp);
50         int ans = 0;
51         for(int i = 0; i < t; ++i)
52         {
53             if(find(a[i].x) != find(a[i].y))
54             {
55                 shu(a[i].x,a[i].y);
56                 ans += a[i].value;
57             }
58         }
59         cout << ans << endl;
60     }
61     return 0;
62 }