use proconio::{fastout, input};

#[fastout]
fn main() {
    input! {
        s: char,
    }

    println!("{}", output(solve(s)));
}

fn solve(s: char) -> &'static str {
    match s {
        'A' => "A#",
        'B' => "C",
        'C' => "C#",
        'D' => "D#",
        'E' => "F",
        'F' => "F#",
        'G' => "G#",
        _ => unreachable!(),
    }
}

fn output(ans: &'static str) -> &'static str {
    ans
}