using System;
using System.IO;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Numerics;
using System.Diagnostics;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using static System.Math;

class P
{
    static void Main()
    {
        Console.WriteLine(".123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960"[int.Parse(Console.ReadLine())]);
    }
}