delete pics to save space

1.3211.cpp

@@ -0,0 +1,50 @@
+#include<cstdio>
+#include<cstring>
+#include<algorithm>
+#include<vector>
+using namespace std;
+const int maxn=205;
+int n,m;
+vector<int> G[maxn],E[maxn];
+double a[maxn][maxn],res=0;
+void solve(int mi)
+{
+	memset(a,0,sizeof(a));
+	int md=1<<mi;
+	for(int i=1;i<n;i++)
+	{
+		a[i][i]=G[i].size();
+		for(int j=0;j<G[i].size();j++)
+			if(E[i][j]&md)
+			{
+				a[i][n+1]=a[i][n+1]+1;
+				a[i][G[i][j]]=a[i][G[i][j]]+1;
+			}
+			else a[i][G[i][j]]=a[i][G[i][j]]-1;
+	}
+	a[n][n]=1; a[n][n+1]=0;
+	for(int i=1;i<=n;i++)
+	{
+		for(int j=i;j<=n;j++) if(a[j][i]!=0) { for(int k=1;k<=n+1;k++) swap(a[i][k],a[j][k]); break; }
+		for(int j=n+1;j>=i;j--) a[i][j]/=a[i][i];
+		for(int j=1;j<=n;j++) if(j!=i) for(int k=n+1;k>=i;k--) a[j][k]-=a[j][i]*a[i][k];
+	}
+	res+=md*a[1][n+1];
+}
+int main()
+{
+	#ifdef local
+	freopen("pro.in","r",stdin);
+	#endif
+	scanf("%d%d",&n,&m);
+	for(int i=0;i<m;i++)
+	{
+		int u,v,w; scanf("%d%d%d",&u,&v,&w);
+		G[u].push_back(v); E[u].push_back(w);
+		if(u!=v) { G[v].push_back(u); E[v].push_back(w); }
+	}
+	for(int i=0;i<30;i++)
+		solve(i);
+	printf("%.3lf\n",res);
+	return 0;
+}