use std::io::stdin;
pub fn main() {
    let n: usize = {
        let mut s = String::new();
        let _ = stdin().read_line(&mut s);
        s.trim().parse().unwrap()
    };
    for i in 0..1000 {
        if n <= 2usize.pow(i) {
            println!("{}", i);
            break;
        }
    }
}