bzoj 3036: 绿豆蛙的归宿

23333sb题都做不对,,,感觉傻傻哒。。。23333333333333,一开始简直是直接真·乱搞啊。。

 1 #include <bits/stdc++.h>
 2 #define LL long long
 3 #define lowbit(x) x&(-x)
 4 #define inf 0x3f3f3f3f
 5 using namespace std;
 6 inline int ra()
 7 {
 8     int x=0,f=1; char ch=getchar();
 9     while (ch<'0' || ch>'9') {if (ch=='-') f=-1; ch=getchar();}
10     while (ch>='0' && ch<='9') {x=x*10+ch-'0'; ch=getchar();}
11     return x*f;
12 }
13 int n,cnt,m;
14 int head[100005],d[100005],in[100005];
15 double f[100005];
16 bool vis[100005];
17 struct edge{
18     int to,next,v;
19 }e[200005];
20 void insert(int x, int y, int v)
21 {
22     e[++cnt].next=head[x]; e[cnt].to=y; e[cnt].v=v; head[x]=cnt; d[x]++; 
23 }
24 void dfs(int x)
25 {
26     if (!vis[x]) vis[x]=1; else return;
27     for (int i=head[x];i;i=e[i].next)
28     {
29         dfs(e[i].to);
30         f[x]+=(double)(f[e[i].to]+e[i].v)/(double)d[x];
31     }
32 }
33 int main(int argc, char const *argv[])
34 {
35     n=ra(); m=ra();
36     for (int i=1; i<=m; i++) 
37     {
38         int x=ra(),y=ra(),v=ra();
39         insert(x,y,v);
40     }
41     dfs(1);    
42     printf("%.2lf\n",f[1]);
43     return 0;
44 }

 

posted @ 2017-03-06 20:50  ws_ccd  阅读(145)  评论(0编辑  收藏  举报