gem install rdata

gem 'rdata'

require 'rdata'

@stack = RData::Stack.new

@stack.push(x) 		# => Returns 'x'
@stack.pop 			# => Returns 'top'
@stack.top 			# => Returns 'top'
@stack.is_empty? 	# => Returns true/false

@queue = RData::Queue.new

@queue.enqueue(9) 	# => Returns '9'
@queue.dequeue 			# => Returns 'head'
@queue.peek 				# => Returns 'head' without removing it
@queue.is_empty? 		# => Returns true/false