use proconio::input;
fn main() {
    input! {
        w:usize,
        h:usize,
        mut word:char,
    }
    for _ in 0..h {
        for _ in 0..w {
            print!("{}", word);
            word = if word == 'B' { 'W' } else { 'B' };
        }
        println!("");
        if w % 2 == 0 {
            word = if word == 'B' { 'W' } else { 'B' };
        }
    }
}