use proconio::input;
fn main() {
    input! {
        w:usize,
        h:usize,
        mut word:char,
    }
    let next:String;
    for _ in 0..h {
        for _ in 0..w {
            print!("{}",word);
            word = if word == 'B' {'W'} else {'B'};
        }
        println!("");
        word = if word == 'B' {'W'} else {'B'};
    }
}