#![allow(unused_imports)]
#![allow(non_snake_case)]
use std::collections::HashMap;
use std::collections::HashSet;
use std::collections::VecDeque;

#[allow(unused_macros)]
macro_rules! read {
    ([$t:ty] ; $n:expr) =>
        ((0..$n).map(|_| read!([$t])).collect::<Vec<_>>());
    ($($t:ty),+ ; $n:expr) =>
        ((0..$n).map(|_| read!($($t),+)).collect::<Vec<_>>());
    ([$t:ty]) =>
        (rl().split_whitespace().map(|w| w.parse().unwrap()).collect::<Vec<$t>>());
    ($t:ty) =>
        (rl().parse::<$t>().unwrap());
    ($($t:ty),*) => {{
        let buf = rl();
        let mut w = buf.split_whitespace();
        ($(w.next().unwrap().parse::<$t>().unwrap()),*)
    }};
}

#[allow(dead_code)]
fn rl() -> String {
    let mut buf = String::new();
    std::io::stdin().read_line(&mut buf).unwrap();
    buf.trim_end().to_owned()
}

fn main() {
    let (x, y, mut h) = read!(f64, f64, f64);
    let (mut x, mut y) = (x * 1000.0, y * 1000.0);
    if x > y {
        std::mem::swap(&mut x, &mut y);
    }
    let mut ans = 0;
    while x > h {
        x /= 2.0;
        h *= 2.0;
        ans += 1;
    }
    while y > h {
        y /= 2.0;
        h *= 2.0;
        ans += 1;
    }

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