io = STDIN
H,W,A,B=io.gets.split.map(&:to_i)
def row(bin)
  ar=[1]*A+[0]*(W-A)
  ar.map!{|n|n^bin}
  ar.join(" ")
end
def upper(i)
  puts row(1)
end
def lower(i)
  puts row(0)
end
B.times do |i|
  upper(i)
end
(H-B).times do |i|
  lower(i)
end
