fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn main() {
    let mut hs: Vec<(&str, u32)> = vec![
        ("A", read()),
        ("B", read()),
        ("C", read()),
    ];

    hs.sort_by(|a, b| (b.1).partial_cmp(&a.1).unwrap());

    for h in hs {
        println!("{}", h.0);
    }
}