#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <set>
using namespace std;

int main(){
	int N;
	cin >> N;
	N *= 100;

	int M = 1000000 - N;
	double ans = (M*0.01)/(N*0.99 + M*0.01);
	printf("%.18f\n", ans*100);

	return 0;
}