1 #include<stdio.h>
2 #include<algorithm>
3 struct Edge
4 {
5 int u,v,w;
6 }edge[10010];
7 int n,m,sett[110];
8 int cmp(const struct Edge x,const struct Edge y)
9 {
10 return x.w < y.w;
11 }
12 int ffind(int x)
13 {
14 if(x != sett[x])
15 x = ffind(sett[x]);
16 return x;
17 }
18 int kruskal()
19 {
20 int i;
21 for(i = 1; i <= n; i++)
22 sett[i] = i;
23 std::sort(edge, edge+m, cmp);
24 int cnt = 0;
25 for(i = 0; i < m; i++)
26 {
27 int x=ffind(edge[i].u);
28 int y=ffind(edge[i].v);
29 if(x!=y)
30 {
31 sett[x] = y;
32 cnt += edge[i].w;
33 }
34 }
35 return cnt;
36 }
37 int main ()
38 {
39 while(~scanf("%d %d",&n,&m))
40 {
41 for(int i = 0;i < m; i++)
42 scanf("%d %d %d",&edge[i].u,&edge[i].v,&edge[i].w);
43 printf("%d\n",kruskal());
44 }
45 return 0;
46 }
