def main():
    H, W, A, B = map(int, input().split())

    for _ in range(H-B):
        print('0'*A+'1'*(W-A))
    for _ in range(B):
        print('1'*A+'0'*(W-A))


if __name__ == "__main__":
    main() def main():
    H, W, A, B = map(int, input().split())

    for _ in range(H-B):
        print('0'*A+'1'*(W-A))
    for _ in range(B):
        print('1'*A+'0'*(W-A)) 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 range(H-B):
        print('0'*A+'1'*(W-A))
     _ range(H-B) range H-B H 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 _ in range(B):
        print('1'*A+'0'*(W-A)) _ range(B) range 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 = map(int, input().split())

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

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

    for _ in range(H-B):
        print('0'*A+'1'*(W-A))
    for _ in range(B):
        print('1'*A+'0'*(W-A))


if __name__ == "__main__":
    main()
