func main()
	var _: [][]char :: cui@input().split(" ")
	var W: int :: _[0].toInt(&)
	var H: int :: _[1].toInt(&)
	var C: []char :: _[2]
	do C :~ [C[0] = 'B' ?('W', 'B')]
	for h(1, H)
		for w(1, W)
			do cui@print([C[(h + w) % 2]])
		end for
		do cui@print("\n")
	end for
	var ans: int
end func