本程序使用C++语言在VC6.0下实现DES加密解密过程，输入明文从文件读取，输出密文写到文件，加密密钥程序内定，可以修改。-This program uses C++ language Under the VC6.0 DES encryption and decryption process, the input plaintext read from the file, the output ciphertext is written to the file encryption key program defaults, you can modify.