fn main() {
    let mut line = String::new();
    std::io::stdin().read_line(&mut line).unwrap();
    let bytes = line.trim().as_bytes();
    let mut ret = String::new();
    for i in 0..bytes.len() {
        ret.push(std::char::from_u32(((bytes[i] as u32) - (i as u32) % 26 - 66 % 26) % 26 + 65).unwrap());
    }
    println!("{}", ret);
}