h, w, a, b = gets.strip.split.map(&:to_i)

result = Array.new(h) { [0]*w }

h.times do |i|
  w.times do |j|
    if i < b && j < a
        result[i][j]=1
    end
    if i >= b && j >= a
        result[i][j]=1
    end
    
  end
end

h.times do |i|
  puts result[i].join('')
end
