hdu1233 还是畅通工程 最小生成树

 1 #include<stdio.h>
 2 #include<string.h>
 3 #include<algorithm>
 4 using namespace std;
 5 
 6 struct seg{
 7     int a,b,l;
 8     bool operator <(const seg a)const{
 9         return l<a.l;
10     }
11 }s[5000];
12 
13 int n,fa[105];
14 
15 void init(){
16     for(int i=1;i<=n;i++)fa[i]=i;
17 }
18 
19 int find(int x){
20     return x==fa[x]?x:fa[x]=find(fa[x]);
21 }
22 
23 int main(){
24     while(scanf("%d",&n)!=EOF&&n!=0){
25         int c=n*(n-1)/2;
26         int i;
27         for(i=1;i<=c;i++){
28             scanf("%d%d%d",&s[i].a,&s[i].b,&s[i].l);
29         }
30         sort(s+1,s+c+1);
31         init();
32         int t=0,ans=0;
33         for(i=1;i<=c;i++){
34             int x=find(s[i].a),y=find(s[i].b);
35             if(x!=y){
36                 ans+=s[i].l;
37                 t++;
38                 fa[x]=y;
39                 if(t==n-1)break;
40             }
41         }
42         printf("%d\n",ans);
43     }
44     return 0;
45 }