简单的卖苹果收银管理源代码，要求程序能正确处理任何数据。当苹果的等级、数量以及顾客的付款不合要求时，通知用户出借，程序结束。-Simple cash register to sell Apple' s management of source code, can correctly handle the claim process any data. When the level of Apple, the number of non-payment, as well as custome