using System;
using System.Collections.Generic;
using System.Linq;
using static System.Console;

class Program
{
    public static void Main()
    {
        var N = int.Parse(ReadLine());
        if (N == 0)
        {
            WriteLine(0);
            return;
        }

        var s = new System.Text.StringBuilder(100000);
        for (int i = 0; i < 100000/6; i++) s.Append("142857");
        s.Append("142857".Substring(0,100000%6));
        WriteLine($"0.{s.ToString().Substring(0, N)}");
    }
}