def main():
    H, W, A, B = (int(i) for i in input().split())
    for i in range(B):
        print("0"*A+"1"*(W-A))
    for i in range(H-B):
        print("1"*A+"0"*(W-A))


if __name__ == '__main__':
    main() def main():
    H, W, A, B = (int(i) for i in input().split())
    for i in range(B):
        print("0"*A+"1"*(W-A))
    for i in range(H-B):
        print("1"*A+"0"*(W-A)) main int(i) for i in input().split() for i in input().split() i input().split() ().split () input split for i in input().split() int(i) int i H, W, A, B = (int(i) for i in input().split()) H (int(i) for i in input().split()) W A B for i in range(B):
        print("0"*A+"1"*(W-A))
     i range(B) range B print("0"*A+"1"*(W-A)) print "0"*A+"1"*(W-A) "0"*A "0" A "1"*(W-A) "1" W-A W A for i in range(H-B):
        print("1"*A+"0"*(W-A)) i range(H-B) range H-B H B print("1"*A+"0"*(W-A)) print "1"*A+"0"*(W-A) "1"*A "1" A "0"*(W-A) "0" W-A W A if __name__ == '__main__':
    main() __name__ == '__main__' __name__ '__main__' main() main def main():
    H, W, A, B = (int(i) for i in input().split())
    for i in range(B):
        print("0"*A+"1"*(W-A))
    for i in range(H-B):
        print("1"*A+"0"*(W-A)) def main():
    H, W, A, B = (int(i) for i in input().split())
    for i in range(B):
        print("0"*A+"1"*(W-A))
    for i in range(H-B):
        print("1"*A+"0"*(W-A)) main
def main():
    H, W, A, B = (int(i) for i in input().split())
    for i in range(B):
        print("0"*A+"1"*(W-A))
    for i in range(H-B):
        print("1"*A+"0"*(W-A))


if __name__ == '__main__':
    main()
