(b) Should we make this << a member or non-member? Private, public, friend, or neither?
Member, public. You create a queue object and overload insertion operator as member function. It can be used to insert characters into the queue.
Reason: We wanted to insert in queue stream and not in external stream such as cout. It is better practice to use Member functions whenever you can. Friends should be used only when members can't be used.
Get_Front() becomes a public member function.