def main():
    h, w, a, b = map(int, input().split())
    s = [[] for _ in [0] * h]
    for i in range(b):
        s[i] = "0" * a + "1" * (w - a)
    for i in range(b, h):
        s[i] = "1" * a + "0" * (w - a)
    for i in s:
        print(i)
main() def main():
    h, w, a, b = map(int, input().split())
    s = [[] for _ in [0] * h]
    for i in range(b):
        s[i] = "0" * a + "1" * (w - a)
    for i in range(b, h):
        s[i] = "1" * a + "0" * (w - a)
    for i in s:
        print(i) main h, w, a, b = map(int, input().split()) h map(int, input().split()) map int input().split() ().split () input split w a b [] for _ in [0] * h for _ in [0] * h _ [0] * h [0] 0 h for _ in [0] * h [] s = [[] for _ in [0] * h] s [[] for _ in [0] * h] for i in range(b):
        s[i] = "0" * a + "1" * (w - a)
     i range(b) range b s[i] = "0" * a + "1" * (w - a) s[i] s i "0" * a + "1" * (w - a) "0" * a "0" a "1" * (w - a) "1" w - a w a for i in range(b, h):
        s[i] = "1" * a + "0" * (w - a)
     i range(b, h) range b h s[i] = "1" * a + "0" * (w - a) s[i] s i "1" * a + "0" * (w - a) "1" * a "1" a "0" * (w - a) "0" w - a w a for i in s:
        print(i) i s print(i) print i main() main def main():
    h, w, a, b = map(int, input().split())
    s = [[] for _ in [0] * h]
    for i in range(b):
        s[i] = "0" * a + "1" * (w - a)
    for i in range(b, h):
        s[i] = "1" * a + "0" * (w - a)
    for i in s:
        print(i) def main():
    h, w, a, b = map(int, input().split())
    s = [[] for _ in [0] * h]
    for i in range(b):
        s[i] = "0" * a + "1" * (w - a)
    for i in range(b, h):
        s[i] = "1" * a + "0" * (w - a)
    for i in s:
        print(i) main
def main():
    h, w, a, b = map(int, input().split())
    s = [[] for _ in [0] * h]
    for i in range(b):
        s[i] = "0" * a + "1" * (w - a)
    for i in range(b, h):
        s[i] = "1" * a + "0" * (w - a)
    for i in s:
        print(i)
main()