package yukicoder;
import java.util.Scanner;
public class Main{
	public static void main(String[] args)throws Exception{
		new Main().solve();
	}
	void solve(){
		Scanner sc=new Scanner(System.in);
		double n=sc.nextDouble();
		n=100*n;
		double total=1000000;
		double ans=0;
		ans+=0.01*(total-n)/total;
		ans=ans/(0.99*n/total+0.01*(total-n)/total);
		System.out.println(ans*100);
	}
}