#include<iostream>
#include<cstdio>
#include<cstring>
#include<queue>
#include<cmath>

using namespace std;

int n,m,e;
int hed[105],vis[105];
double dis[105];

struct st{
    int v,nex;
    double w;
}edge[20005];

void add(int u,int v,double w){
    edge[e].v=v,edge[e].w=w,edge[e].nex=hed[u],hed[u]=e++;
}
double spfa(){
    for(int i=1;i<=n;i++)dis[i]=0.0,vis[i]=0;dis[1]=1;
    priority_queue<pair<double,int> >q;
    q.push(make_pair(dis[1],1));
    while(!q.empty()){
        int u = q.top().second;q.pop();
        if(vis[u])continue;vis[u]=1;
        for(int i=hed[u];~i;i=edge[i].nex){
            int v = edge[i].v;
            if(dis[v]<dis[u]*edge[i].w){
                dis[v]=dis[u]*edge[i].w;
                if(!vis[v])
                {
                    q.push(make_pair(dis[v],v));
                }
            }
        }
    }
    return dis[n]*100.0;
}


int main()
{
    while(cin>>n,n){
        cin>>m;
        memset(hed,-1,sizeof(hed));
        e=1;
        while(m--){
            int u,v;scanf("%d%d",&u,&v);
            double w;scanf("%lf",&w);
            w=w/100.0;
            add(u,v,w);
            add(v,u,w);
        }
       printf("%.6lf percent\n",spfa());

    }
    return 0;
}