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

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

print('\n'.join(ans))
      
