???????????? ?????????? ??? ??? ?? ??? ??? ???? ??? ???????????!??????? ??? ????? ????? ? ???? ??? ??????????? ???? ?????????;?? ???? ??? ???????? ?? ????????? ?? ???????? ????? ?? ?????????? ??? ?? ??????? ??? ??????? ??? ????? ??????????? ???? ?? ??????? ??? ???????????.?????? - ????? ????? ?? ????? ??????? ?? ??? ??? ??????4x4 parity occurs on t