h, w, a, b = map(int, input().split())
for i in range(h):
  s = [0]*a+[1]*(w-a)
  t = [1]*a+[0]*(w-a)
  if i < b:
    print("".join(map(str, s)))
  else:
    print("".join(map(str, t))) h, w, a, b = map(int, input().split()) h map(int, input().split()) map int input().split() ().split () input split w a b for i in range(h):
  s = [0]*a+[1]*(w-a)
  t = [1]*a+[0]*(w-a)
  if i < b:
    print("".join(map(str, s)))
  else:
    print("".join(map(str, t))) i range(h) range h s = [0]*a+[1]*(w-a) s [0]*a+[1]*(w-a) [0]*a [0] 0 a [1]*(w-a) [1] 1 w-a w a t = [1]*a+[0]*(w-a) t [1]*a+[0]*(w-a) [1]*a [1] 1 a [0]*(w-a) [0] 0 w-a w a if i < b:
    print("".join(map(str, s)))
  else:
    print("".join(map(str, t))) i < b i b print("".join(map(str, s))) print "".join(map(str, s)) "".join "" join map(str, s) map str s print("".join(map(str, t))) print "".join(map(str, t)) "".join "" join map(str, t) map str t s = [0]*a+[1]*(w-a) [0]*a+[1]*(w-a) s w, a, b = map(int, input().split()) map(int, input().split()) w a, b = map(int, input().split()) map(int, input().split()) a b = map(int, input().split()) map(int, input().split()) b h, w, a, b = map(int, input().split()) map(int, input().split()) h t = [1]*a+[0]*(w-a) [1]*a+[0]*(w-a) t
h, w, a, b = map(int, input().split())
for i in range(h):
  s = [0]*a+[1]*(w-a)
  t = [1]*a+[0]*(w-a)
  if i < b:
    print("".join(map(str, s)))
  else:
    print("".join(map(str, t)))