func main()
	var W: int :: cui@inputInt()
	var H: int :: cui@inputInt()
	var c: char :: cui@inputChar()
	var cc: []char :: #[2]char
	do cc[0] :: c
	do cc[1] :: c = 'B' ?('W', 'B')
	
	for h(1, H)
		var line: []char :: #[W]char
		for w(1, W)
			do line[w - 1] :: cc[(h + w) % 2]
		end for
		do cui@print("\{line}\n")
	end for
end func