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