using System;

class MagicPocket
{
	static void Main(string[] args)
	{
	    double i = int.Parse(Console.ReadLine());
	    int biscuit = 1;
	    int hisCount = 0;
	    while (biscuit < i)
	    {
	        biscuit = biscuit * 2;
	        hisCount++;
	    }
    	Console.WriteLine(hisCount);
	}
}