fn main() {
    let s = (0..3).filter(|_| {
        let mut s = String::new();
        std::io::stdin().read_line(&mut s).ok();
        let s = s.trim();
        s == "RED"
    })
    .count();
    if s <= 1 {
        println!("BLUE");
    } else {
        println!("RED");
    }
}