题目：有两个磁盘文件A和B,各存放一行字母，要求把这两个文件中的信息合并（按字母顺序排列），

　　　 输出到一个新文件C中。

-Topic: there are two disk file A and B, each deposit A line letters and asked to the two files with the information (in alphabetical order),

The output to a new file C.