设计一个用于管理朋友信息的程序。将朋友信息（年龄、姓名、电话）存放在MyFrd.dat中，从文件读出这些信息并显示，并能按姓名(要求可简化输入，如只输入姓氏便可查询)进行查询，将查询信息输出屏幕。-The design of a friend used to manage information. Will be a friend information (age, name, phone number) stored in MyFrd.dat, from paper to read out t

外部存储器驱动，有外部声明函数，方便调用，简化代码编写时间-External memory drive, external function declarations, easy call, to simplify coding time

ad采样器驱动，有外部声明函数，方便调用，简化代码编写时间-ad sampler drive, external function declarations, easy call, to simplify coding time

MIFare is a technology that allows a contactless transmission of data between a battery-less memory card and a card reader. MiFare is widely used for ticketing (Oyster card at London underground) or for access control. The helper class introduced in