最小生成树 kruskal算法

 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 }