H, W, A, B = gets.split.map(&:to_i)

d = 1

B.times {
	A.times { print d }
	d ^= 1
	(W-A).times { print d }
	d ^= 1
	puts
}
(H-B).times {
	d ^= 1
	A.times { print d }
	d ^= 1
	(W-A).times { print d }
	puts
}
