ϺF(xin)I(y)W(xu)Ժ
ͲI(y)W(xu)ԺD^
ur(nng)I(y)W(xu)D^
(j)W(xu)ԺD^
ɽ|W(xu)D^
ɽ|r(nng)I(y)W(xu)D^