自制自动售货机。分为两个部分，一个是前台销售操作，一个后台管理操作。前台销售是销售产品和找零等操作，后台管理是修改密码，增加产品等操作。-Homemade vending machines. Divided into two parts, one is the front sales operation, a backstage management operations. Front sales are sales of products and give change and other operations, back office management is to change the password, increase product and other operations.