using System;

class yukicoder
{
static void Main(string[] args)
{
        var r = new Reader();
        var N = r.nextInt();
        int i = 0;
        while (true)
        {
            if ( Math.Pow(2, i) >= N )
            {
                Console.WriteLine(i);
                break;
            }
            ++i;
        }
}
}

class Reader
{
    string[] s;
    int i;
    char[] cs = new char[] { ' ' };

    public Reader()
    {
        s = new string[0];
        i = 0;
    }

    public string next()
    {
        if ( i < s.Length )
            return s[i++];
        var input = Console.ReadLine();
        while ( input == "" )
            input = Console.ReadLine();
        s = input.Split(cs, StringSplitOptions.RemoveEmptyEntries);
        i = 0;
        return next();
    }

    public int nextInt()
    {
        return int.Parse(next());
    }

}