fn run() {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).unwrap();
    let mut it = s.trim().split_whitespace();
    let x: u64 = it.next().unwrap().parse().unwrap();
    let y: u64 = it.next().unwrap().parse().unwrap();
    let h: u64 = it.next().unwrap().parse().unwrap();
    let (mut x, mut y, mut h) = ((x * 1000) << 20, (y * 1000) << 20, h << 20);
    if x > y {
        std::mem::swap(&mut x, &mut y);
    }
    let mut ans = 0;
    while x > h {
        x /= 2;
        h *= 2;
        ans += 1;
    }
    while y > h {
        y /= 2;
        h *= 2;
        ans += 1;
    }
    println!("{}", ans);
}

fn main() {
    run();
}