rt，玄关

#include<algorithm>
#include<iostream>
#include<cstring>
#include<cmath>
#include<cstdio>
#include<stack>
#include<queue>
#include<iomanip>
#define debug() cout<<"qwq"<<endl
using namespace std;

const int N=2e5+10;
int n,m,s,ed;

struct node{
	int v,nxt;
	double w;
}eg[N];
struct aa{
	double dist;
	int idx;
	const bool operator > (const aa &t)const{
		return t.dist<dist;
	}
};
int hd[N],cnt;
void add(int a,int b,int c)
{
	cnt++;
	eg[cnt].v=b;
	eg[cnt].nxt=hd[a];
	eg[cnt].w=(100-c)/100.0;
	hd[a]=cnt;
}
double dis[N];

bool vis[N];
void dij()
{
	priority_queue<aa,vector<aa>,greater<aa> >q;
	q.push(aa{0,s});
	vis[s]=true;
	while(!q.empty())
	{
		aa nw=q.top();	
		q.pop();
		vis[nw.idx]=false;
		
		for(int i=hd[nw.idx];i;i=eg[i].nxt)
		{
			int to=eg[i].v;
			if(dis[to] < dis[nw.idx]*eg[i].w)
			{
				dis[to]=dis[nw.idx]*eg[i].w;
				if(!vis[to]) q.push(aa{dis[to],to}),vis[to]=true;
			}	
		}
	}
}

int main()
{	
	freopen("P1576_9.in","r",stdin);
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	memset(dis,0,sizeof dis);
	cin>>n>>m;
	int x,y,z;
	for(int i=1;i<=m;i++)
	{
		cin>>x>>y>>z;
		add(x,y,z);
		add(y,x,z);
	}
	cin>>s>>ed;
	dis[s]=1.0;
	dij();
	cout<<fixed<<setprecision(8)<<100.0/dis[ed]<<endl;
	cout<<endl;
	return 0;
}

P.S 第九个点本地跑了7s