import sys
 
stdin = sys.stdin
 
ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()
nas = lambda: stdin.readline().split()

h, w, a, b = na()
d1 = [1, 0]
d2 = [0, 1]

c = d1
for i in range(h):
    if i == b:
        c = d2
    for j in range(w):
        if j >= a:
            print(c[1], end='')
        else:
            print(c[0], end='')
    print() import sys sys stdin = sys.stdin stdin sys.stdin sys stdin ni = lambda: int(ns()) ni lambda: int(ns()) int(ns()) int ns() ns na = lambda: list(map(int, stdin.readline().split())) na lambda: list(map(int, stdin.readline().split())) list(map(int, stdin.readline().split())) list map(int, stdin.readline().split()) map int stdin.readline().split() stdin.readline().split stdin.readline() stdin.readline stdin readline split ns = lambda: stdin.readline().rstrip() ns lambda: stdin.readline().rstrip() stdin.readline().rstrip() stdin.readline().rstrip stdin.readline() stdin.readline stdin readline rstrip nas = lambda: stdin.readline().split() nas lambda: stdin.readline().split() stdin.readline().split() stdin.readline().split stdin.readline() stdin.readline stdin readline split h, w, a, b = na() h na() na w a b d1 = [1, 0] d1 [1, 0] 1 0 d2 = [0, 1] d2 [0, 1] 0 1 c = d1 c d1 for i in range(h):
    if i == b:
        c = d2
    for j in range(w):
        if j >= a:
            print(c[1], end='')
        else:
            print(c[0], end='')
    print() i range(h) range h if i == b:
        c = d2
     i == b i b c = d2 c d2 for j in range(w):
        if j >= a:
            print(c[1], end='')
        else:
            print(c[0], end='')
     j range(w) range w if j >= a:
            print(c[1], end='')
        else:
            print(c[0], end='')
     j >= a j a print(c[1], end='') print c[1] c 1 end='' end '' print(c[0], end='') print c[0] c 0 end='' end '' print() print h, w, a, b = na() na() h stdin = sys.stdin sys.stdin stdin d1 = [1, 0] [1, 0] d1 w, a, b = na() na() w c = d1 d1 c na = lambda: list(map(int, stdin.readline().split())) lambda: list(map(int, stdin.readline().split())) na nas = lambda: stdin.readline().split() lambda: stdin.readline().split() nas b = na() na() b a, b = na() na() a ns = lambda: stdin.readline().rstrip() lambda: stdin.readline().rstrip() ns d2 = [0, 1] [0, 1] d2 c = d2 d2 c ni = lambda: int(ns()) lambda: int(ns()) ni
import sys
 
stdin = sys.stdin
 
ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()
nas = lambda: stdin.readline().split()

h, w, a, b = na()
d1 = [1, 0]
d2 = [0, 1]

c = d1
for i in range(h):
    if i == b:
        c = d2
    for j in range(w):
        if j >= a:
            print(c[1], end='')
        else:
            print(c[0], end='')
    print()