fn main() {
    let mut xx = String::new();
    std::io::stdin().read_line(&mut xx).ok();
    let mut xx: Vec<u64> = xx.split_whitespace().flat_map(str::parse).collect();

    xx.sort_unstable();

    println!("{}", (xx[2] - xx[1]).min(xx[1] - xx[0]));
}