???? ??? ?????? ???? ??? ?????? ???? ??? ?????? ???? ??? ?????? ???? ??? ?????? ???? ??? ?????? ???? ??? ?????? ???? ??? ?????? ???? ??? ?????? ???? ??? ?????? prev?????? ??????? ???????? ?? ????? ???????? ????? ?????? ?????? ?????? ??????? ?????????. ???? ?????? ?? ??????? ?????? ????? ??????? ???????? ????????? ??? ????????? ??????? ???????? ???