OJ-Problems-Source/HDOJ/3696_autoAC.cpp
2016-09-04 14:13:02 +08:00

78 lines
1.6 KiB
C++

#include<cstdio>
#include<cstring>
#include<cmath>
#define N 10005
using namespace std;
int n,m,num,adj[N],q[N];
bool f[N];
double low[N],p[N],w[N];
struct edge
{
int v,pre;
double w;
edge(){}
edge(int vv,double ww,int p){v=vv;w=ww;pre=p;}
}e[N*5];
void insert(int u,int v,double w)
{
e[num]=edge(v,w,adj[u]);
adj[u]=num++;
}
void spfa(int x)
{
int i,v,head=0,tail=0;
memset(f,0,sizeof(f));
memset(low,-0x3f,sizeof(low));
low[x]=0;
q[++tail]=x;
while(head!=tail)
{
x=q[head=(head+1)%N];
f[x]=0;
for(i=adj[x];~i;i=e[i].pre)
if(low[v=e[i].v]<low[x]+e[i].w)
{
low[v]=low[x]+e[i].w;
if(!f[v])
{
f[v]=1;
q[tail=(tail+1)%N]=v;
}
}
}
}
int main()
{
while(scanf("%d",&n),n)
{
int i,k,a,b;
double t,ans=0;
num=0;
memset(adj,-1,sizeof(adj));
for(i=1;i<=n;i++)
scanf("%lf%lf",p+i,w+i);
scanf("%d",&m);
while(m--)
{
scanf("%d",&k);
scanf("%d",&a);
for(i=1;i<k;i++)
{
scanf("%lf%d",&t,&b);
insert(b,a,log(t));
a=b;
}
}
for(i=1;i<=n;i++)
insert(0,i,log(p[i]));
spfa(0);
for(i=1;i<=n;i++)
{
if(p[i]<exp(low[i]))
p[i]=exp(low[i]);
ans+=p[i]*w[i];
}
printf("%.2f\n",ans);
}
}