编写简单的加密程序它把一个文件的所有字母按下列规律进行

换，非字母的字符保持不变。文本可以自行创建，文件名可以自定

转换规律：‘A’→‘Z’，‘B’→‘Y’，• •

-The preparation of a simple encryption program it to a file of all the letters according to the following rules of conduct for non-letter characters remain unchanged. Text can be created, the file name can be self-conversion law:　A →　Z,　B →　Y,