import Data.List
import Control.Monad

f :: String -> Char
f "W" = 'B'
f "B" = 'W'
f  _  = '@'

g :: String -> Char
g "W" = 'W'
g "B" = 'B'
g  _  = '@'

main :: IO ()
main = do
    [a, b, c] <- words <$> getLine
    let w = (read :: String -> Int) a
        h = (read :: String -> Int) b
    forM_ [1..h] $ \i -> do
        if i `mod` 2 == 1
            then putStrLn $ intersperse (f c) $ replicate ((w + 1) `div` 2) (g c)
            else putStrLn $ intersperse (g c) $ replicate ((w + 1) `div` 2) (f c)