use std::io;

const CHARS: [char; 2] = ['B', 'W'];

fn main() {
    let mut input = String::new();
    io::stdin().read_line(&mut input).ok();
    let mut input = input.split_whitespace();
    let w = input.next().unwrap().parse::<usize>().unwrap();
    let h = input.next().unwrap().parse::<usize>().unwrap();
    let d = match input.next().unwrap() {
        "B" => 0,
        "W" => 1,
        _ => unreachable!(),
    };

    for y in 0..h {
        for x in 0..w {
            print!("{}", CHARS[(x + y + d) % 2]);
        }
        println!();
    }
}