using System;

class Program
{
    public static void Main(string[] args)
    {
        int n = int.Parse(Console.ReadLine());
        if (n == 1)
        {
            Console.WriteLine(0);
            return;
        }
        bool[] bits = new bool[32];
        int maxBits = 0;
        for(int i = 0; i < 32;i++)
        {
            if ((n & (1 << i)) == 1 << i)
            {
                bits[i] = true;
                maxBits = Math.Max(maxBits, i);
            }
        }
        bool hasMore = false;
        for (int i = maxBits-1; i >= 0; i--)
        {
            if (bits[i])
            {
                hasMore = true;
            }
        }
        if (hasMore)
        {
            Console.WriteLine(maxBits+1);
            return;
        }
        Console.WriteLine(maxBits);
    }
}