using System;

namespace StudyApp
{
    class Program
    {
        static void Main(string[] args)
        {
            var demand = int.Parse(Console.ReadLine());
            int num = 1;
            int count = 0;

            while (demand > num)
            {
                num *= 2;
                count++;
            }
            Console.WriteLine(count);
        }
    }
}