using System;

namespace No756_Champernowne
{
    class Program
    {
        static void Main(string[] args)
        {
            int d = int.Parse(Console.ReadLine());
            string c = "";

            for (int i = 1; i <= 100; i++)
                c += i.ToString();

            Console.WriteLine(c[d - 1].ToString());
        }
    }
}