.NET???Stack<T>??Queue<T>?????

?????????????????????й???????????Dequeue????????????????ж????_size????0?????????????????????????????0??????_array[_head]????????????????????default(T)???_array[_head]??λ?á????????????????е????????????????_head+=1????????????_head=(_head+1)%_array.Length????????????_head?п???????±??3??λ?????????????_head += 1???4????????????????С??Χ????_head=(_head+1)%_array.Length???0????????????????λ??????????????е??????????????????檔
???????????????Enqueue(T item)???????????н??????Queue??????????????????q.Enqueue("f")???????????????????????_array???????????????????????????Stack????????????????????????????????????Stack?????鸴????????Щ?????????????

??????Stack<T>????????Queue<T>??????????????????????????????鸴??????????Queue??????????????????????????Queue(int capacity)?????????????????п??????????????????????????????capacity?????????