题目：文件操作。具体要求：用户输入源文件名和目的文件名后，若用户缺省目的文件名，则与源文件同名。目的文件不存在时，出现文件复制对话框如下： 1 文件原样复制。2 文件压缩复制。3 文件加密复制 。请选择（1，2，3）：文件压缩复制的含义：将源文件中的所有空格删除后拷贝到目的文件 。加密解密方法：输入一个6字符的密钥，将文件数据和密钥（ASCII码）进行异或运算。 不足6字节的部分，和密钥相应的字符进行运算。（可以设计出更好的压缩和加密/解密算法）

-Topic: File operation. Specific requirements: the user to enter source file name and destination file name, the default destination file name if the user is the same name as the source file. Purpose of the file does not exist, copy the file dialog box appears as follows: 1 file copied. 2 files compressed copy. 3 file encryption replication. Please choose (1,2,3): the meaning of the copied file compression: The source file copies of all the spaces removed to the destination file. Encryption and decryption: a 6-character input key data and key files (ASCII code) for XOR. Less than 6 bytes of the section, and key characters in the corresponding operations. (You can design a better compression and encryption/decryption algorithm)