Edit stack code to make queue

Quote:

Originally Posted by mikeman

I'm attempting to alter a stack class and make it a queue. I don't think it should be that difficult, as I'm essentially changing it from first in last out (stack) to first in first out (queue).

It is not quite so easy, methinks. The stack class that you have is implemented with a fixed size array. It is rather easy to implement a stack like this because you just need to add/remove elements from the end of the array by keeping track of the array size (and copying new elements, of course).

But with a queue, this becomes problematic: you need to implement a ring buffer, or periodically shift elements (which tends to be slow), otherwise your queue's maximum size would be reduced as elements are removed from the queue, until you eventually have a queue that cannot store anything. You may find it easier to use a tailed singly linked list instead.

(That said, std::queue uses a std::deque by default, as does std::stack.)