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

class Magatro
{
    static void Main()
    {
        Console.WriteLine(calc(int.Parse(Console.ReadLine())));
    }
    static int calc(int n)
    {
        int cnt = 0;
        for (cnt = 0; Math.Pow(2, cnt) < n; cnt++)
        {

        }
        return cnt;
    }
}