inputs = gets.split.map(&:to_s)
k = 0
if inputs[2] == "B"
	color1 = "B"
	color2 = "W"
else
	color1 = "W"
	color2 = "B"
end

for i in 1..inputs[1].to_i
	for j in 1..inputs[0].to_i
		k += 1
		if k.odd? == true
			print color1
		else
			print color2
		end
	end
	puts ""
	if inputs[0].to_i % 2 == 0
		k += 1
	end
end