Помогите, пожалуйста, написать функцию, инвертирующую очередь в классе QueueInt.
Вот программа:

#include<iostream.h>
#include<conio.h>
enum BOOL {false, true};
//------------------------------------------------------------------
class List
{
int data;
List *next, *prev;
int Get() {return data;}
public:
List(const int d)
{
data=d;
next=prev=NULL;
}
friend class ListInt;
friend class QueueInt;
friend ostream & operator<<(ostream&, ListInt*);
friend istream & operator>>(istream&, ListInt*);
};
//------------------------------------------------------------------
class ListInt
{
protected:
List *back, *front, *token;
friend ostream & operator<<(ostream&, ListInt*);
friend istream & operator>>(istream&, ListInt*);
public:
ListInt()
{
back=front=token=NULL;
}
void PutToken(int val)
{
List *p = new List(val);
if(empty())
front=back=p;
else
{
back->next=p; p->prev=back;
back=p;}
}
virtual int GetToken()
{
if(token==NULL) token=front;
if(token)
{
int rv=token->data;
token=token->next;
return rv;
}
else return 0;}
BOOL empty()
{return front==NULL? true:false;}
};
//------------------------------------------------------------------
class QueueInt: public ListInt
{
int GetToken();
};
//------------------------------------------------------------------
ostream & operator<<(ostream& os, ListInt*q)
{
os<<"<";
do
{
if(!q->empty())
os<<q->GetToken()<<",";
}
while(q->token);
return os<<">"<<endl;
}
//---------------------------------------------------------------
istream & operator>>(istream& is, ListInt*q)
{
int a; int k;
cout<<"‘Є®«мЄ® н«Ґ¬Ґ­в®ў Ўг¤ҐвҐ ўў®¤Ёвм? ";
is>>k;
for(int i=0; i<k; i++)
{
cout<<i+1<<": ";
is>>a;
q->PutToken(a);
}
return is;
}
//---------------------------------------------------------------------------
int QueueInt::GetToken()
{
if(token==NULL) token=back;
if(back)
{
back=back->prev;
if(back)
{
back->next=NULL;
}
else front=NULL;
int retval=token->data;
delete token;
token=back;
return retval;
}
else return 0;
}
//-----------------------------------------------------------------
int main()
{
clrscr();
ListInt* lst=new ListInt;
cin>>lst;
cout<<"Список:\n";
cout<<lst;
ListInt*och;
cout<<"Очередь:\n";
cout<<och;
getch();
return 0;
}