using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace pj13
{
    class Program
    {
        static void Main(string[] args)
        {
            int N = int.Parse(Console.ReadLine());

            int cookie = 1;
            int count = 0;
            while(cookie < N)
            {
                cookie *= 2;
                count++;
            }
            Console.WriteLine(count);
        }
    }
}