#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#undef _P
#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<to;x++)
#define FORR(x,arr) for(auto& x:arr)
#define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
//-------------------------------------------------------

int N,M;
int mat[21][21];
int rr[21][21];
double pat[21];

void solve() {
	int i,j,k,l,r,x,y,z; string s;
	
	cin>>N>>M;
	FOR(i,N) FOR(j,N) mat[i][j]=100;
	FOR(i,N) mat[i][i]=0;
	
	FOR(i,M) {
		cin>>x>>y>>r;
		rr[x][y]=r;
		mat[x][y]=1;
	}
	FOR(z,N) FOR(x,N) FOR(y,N) mat[x][y]=min(mat[x][y],mat[x][z]+mat[z][y]);
	
	pat[0]=1;
	for(i=1;i<=20;i++) {
		FOR(x,N) if(mat[0][x]==i) {
			pat[x]=1;
			FOR(y,N) if(mat[y][x]==1) {
				pat[x] *= (100-pat[y]*rr[y][x])/100.0;
			}
			pat[x]=1-pat[x];
		}
	}
	_P("%.12lf\n",pat[N-1]);
	
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false);
	FOR(i,argc-1) s+=argv[i+1],s+='\n';
	FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	solve(); return 0;
}