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 the information and display, and by name (required simplify input, enter a last name can only query) query, the query information output screen.