???????? ?????????????????? ???????????? ???????? ???? ????, ???? ???? ???? ????(????)????, ??????????? ????? ????(???? ???? ???? ???????? ???? ?????? ????????????????? ?? ???????? ?????????????????????????? ?? ???????? ?? ?? ??? ???????? ????= ?? ????+ ????? (???????? ???? ??????)??????? ???????? ???????? ?? ????????????????????????????? ?????? ??