use std::io::{self, Read};

fn read_stdin() -> Vec<String> {
    let mut buffer = String::new();
    io::stdin().read_to_string(&mut buffer).ok();
    buffer.trim().split('\n').map(|s| s.to_string()).collect()
}

fn main() {
    let input = read_stdin();
    let n = *&input[0].parse::<usize>().unwrap();

    let mut x: usize = 0;

    while n > 1 << x {
        x += 1;
    }

    println!("{}", x);
}