公司有普通大巴，中巴和空调大巴，中 巴四种类型，每种车型有30辆，每两辆车中有一辆无人售票车．现在公交公司要给这些车编上序号，要能区分车型和售票类型，至少需要多少位号码？　

诗歌鉴赏

                                                                                                                春望
                                                                                                 国破山河在，城春草木深。
                                                                                                 感时花溅泪，恨别鸟惊心。
                                                                                                 烽火连三月，家书抵万金。
                                                                                                 白头搔更短，浑欲不胜簪。