lz样例都没过，交了一发竟然过了，答案让保留八位，但我的从第二位小数开始就与样例有差

所以是数据水还是评测方式的问题？

代码如下

#warning By KonjAC_xrs
#warning ( testing == 0 ) ? Yes : No

#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define ld long double
using namespace std;

inline ll read()
{
    ll x=0,f=1; char ch=getchar();
    while (!isdigit(ch)) {if(ch=='-') f=-1; ch=getchar();}
    while ( isdigit(ch)) {x = x * 10+ch-48; ch=getchar();}
    return x*f;
}

inline void xrs(ll x)
{
    if(x<0) putchar('-') , x=-x;
    if(x>9) xrs(x/10);
    putchar(x%10+'0');
}

const ll inf=1e17;
//const ll mod=;
const ll nore=2e5+20;

ll n,m;
ll pre[nore],ok[nore];

ll tot,ver[nore<<1],head[nore],edge[nore<<1],nxt[nore<<1];
inline void add(ll x,ll y,ll z)
{
	ver[++tot]=y;
	edge[tot]=z;
	nxt[tot]=head[x];
	head[x]=tot;
}

ll d[nore];
bool vis[nore];
inline void dij(ll s)
{
	for(register ll i=1;i<=n;i++)
		d[i]=inf , vis[i]=0;
	priority_queue < pair < ll , ll > > q;
	d[s]=0;
	q.push(make_pair(0,s));
	while(!q.empty())
	{
		ll x=q.top().second;
		q.pop();
		if(vis[x]) continue;
		vis[x]=1;
		for(register ll i=head[x];i;i=nxt[i])
		{
			ll y=ver[i]; ll z=edge[i];
			if(d[y]>d[x]+z)
			{
				d[y]=d[x]+z;
				pre[y]=x;
				ok[y]=z;
				q.push(make_pair(-d[y],y));
			}
		}
	}
}

int main()
{
//	freopen(".in","r",stdin);
//	freopen(".out","w",stdout);
	n=read(); m=read();
	for(register ll i=1;i<=m;i++)
	{
		ll u=read(); ll v=read(); ll z=read();
		add(u,v,z); add(v,u,z);
	}
	
	ll a=read(); ll b=read();
	dij(a);
	
	ll tmp=b;
	double ans=100.0;
	
//	puts("");
//	xrs(pre[tmp]);
//	puts("");
	
	while(pre[tmp]!=a)
	{
		ans/=(double)(1-(double)ok[tmp]*0.01);
		tmp=pre[tmp];
	}
	ans/=(double)(1-(double)ok[tmp]*0.01);
	
	printf("%.8f",ans);
	
    getchar();
    return 0;
}
/*
	a*(1-z*0.01)=b , 
	b/(1-z*0.01)=a ;
*/

My ans is

103.09278351

The yangli is

103.07153164