delete pics to save space

p.CH3802.cpp

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+//http://contest-hunter.org:83/contest/0x30%E3%80%8C%E6%95%B0%E5%AD%A6%E7%9F%A5%E8%AF%86%E3%80%8D%E4%BE%8B%E9%A2%98/3802%20%E7%BB%BF%E8%B1%86%E8%9B%99%E7%9A%84%E5%BD%92%E5%AE%BF
+#include<cstdio>
+#include<cstring>
+#include<algorithm>
+#include<queue>
+using namespace std;
+const int maxn=100005;
+struct Edge { int v,w; Edge *nxt; };
+Edge mem[maxn*2],*G[maxn],*ecnt=mem;
+inline void AddEdge(int u,int v,int w) { ecnt->v=v; ecnt->w=w; ecnt->nxt=G[u]; G[u]=ecnt++; }
+int deg[maxn],in[maxn];
+int n,m;
+double f[maxn];
+queue<int> Q;
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d%d",&n,&m);
+	for(int i=1;i<=m;i++)
+	{
+		int x,y,z;  scanf("%d%d%d",&x,&y,&z);
+		AddEdge(y,x,z);
+		in[x]++; deg[x]++;
+	}
+	Q.push(n);
+	while(Q.size())
+	{
+		int u=Q.front(); Q.pop();
+		for(Edge *it=G[u];it;it=it->nxt)
+		{
+			f[it->v]+=(f[u]+it->w)/deg[it->v];
+			in[it->v]--;
+			if(in[it->v]==0) Q.push(it->v);
+		}
+	}
+	printf("%.2lf\n",f[1]);
+}