#
# This file contains the Ruby code from Program 6.1 of
# "Data Structures and Algorithms
# with Object-Oriented Design Patterns in Ruby"
# by Bruno R. Preiss.
#
# Copyright (c) 2004 by Bruno R. Preiss, P.Eng.  All rights reserved.
#
# http://www.brpreiss.com/books/opus8/programs/pgm06_01.txt
#
class Stack < Container

    def initialize
	super
    end

    abstractmethod :push

    abstractmethod :pop

    abstractmethod :top

end