using System;
using System.Numerics;

public class Hello
{
    public static void Main()
    {
        var s = "";
        for (int i = 1; i <= 99; i++) s += i.ToString();
        s += "1";
        var n = int.Parse(Console.ReadLine().Trim());
        BigInteger a = BigInteger.Parse(s) * n;
        var s2 = a.ToString();
        writeAns(s2, getK(n));
    }
    public static void writeAns(string s, int n)
    {
        var ans = "";
        if (n == 0) ans = "0." + s;
        else ans = s.Substring(0, n) + "." + s.Substring(n);
        Console.WriteLine(ans);
    }

    public static int getK(int n)
    {
        var s = 0.12345d;
        var a = s * n;
        if (a >= 100) return 3;
        else if (a >= 10 && a < 100) return 2;
        else if (a >= 1 && a < 10) return 1;
        else return 0;
    }
}