class Manage:
   def __init__(self):
      self.data = [18, 93, 3, 82, 76, 5, 9]
      self.commandStack = []
   def display(self):
      for x in self.data: print x, "\t",
      print
   def run(self):
      while 1:
         cmd = raw_input("Type a command: ") 
         if cmd == "quit" or cmd == "exit": break
         elif cmd == "print": self.display()
         elif cmd == "undo":
            cmd = self.commandStack[0]
            self.commandStack.pop(0)
            cmd.undo(self.data)
         elif cmd == "remove":
            cmd = RemoveCommand()
            cmd.execute(self.data)
            self.commandStack = [cmd] + self.commandStack

class Command:
   def __init__(self, n):
      self.name = n
   def execute(self, data): pass
   def undo(self): pass
   def __repr__(self):
      return self.name

class RemoveCommand(Command):
   def __init__(self):
      Command.__init__(self, "Remove")
      self.key = int(raw_input("Type number to remove: "))
   def undo(self, data):
      data.insert(self.key)
   def execute(self, data):
      print "Removing: ", self.key
      data.remove(self.key)
      
if __name__ == "__main__":
   man = Manage()
   man.run()