The QStack class is a template class that provides a stack. ... QStack  ( const QStack<type> & s )  . ... QStack<type>&  operator=  ( const QStack<type> & s )  . ... type*  top  () const . operator  type*  ()const . ... A stack is a collection that can be used to push and pop items. ... Returns a reference to the top item on the stack (most recently pushed). ... Removes the top item from the stack and returns it. ... Removes the top item from the stack and deletes it if if autoDelete () is TRUE. ...