C # no Lock queue

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;usingSystem.Threading;usingSystem.Threading.Tasks;namespacejf_lockfreequeue{ Public classLockfreequeue<t>    {        Private classNode<t>        {             PublicT value;  PublicNode<t>Next; }        PrivateNode<t>Head; PrivateNode<t>tail; Private intcount;  PublicLockfreequeue () {head=NewNode<t>(); Tail=Head; }         Public intCount {Get{returncount;} }         Public voidEnQueue (T item) {varnode =NewNode<t>(); Node.value=item; Node.next=NULL; Node<T> Tmptail =NULL; BOOLIsreplace =false;  Do{Tmptail=tail;  while(Tmptail.next! =NULL) {Tmptail=Tmptail.next; }                varresult = Interlocked.compareexchange<node<t>> (refTmptail.next, node,NULL); Isreplace= result! =Tmptail.next; }  while(!isreplace); Interlocked.exchange<Node<T>> (reftail, node); Interlocked.Increment (refcount); }         PublicT Dequeue () {BOOLIsreplace =false; Node<T> Tmphead =NULL; Node<T> Oldheadnext =NULL;  Do{Tmphead=Head; Oldheadnext=Tmphead.next; if(Oldheadnext = =NULL)                {                    return default(T); }                Else                {                    varresult = Interlocked.compareexchange<node<t>> (refHead, Oldheadnext, Tmphead); Isreplace= result! =Oldheadnext; }            }  while(!isreplace); Interlocked.decrement (refcount); returnOldheadnext.value; }    }}

C # no Lock queue