用C语言求解经典逻辑推理题

创建一个经过加密的软件系统信息文件，在软件启动时会校验这些信息，判断是授权用户在使用该软件。-create an encrypted document information system software, the software will start checking the information, and judgment is authorized users in the use of the software.

DES加密算法及详细说明（HTM）

这段代码适用于matlab的ECC加密。它包含ECC加密算法的所有必要活动；

简单的文件加密代码 一个不错的文件加密系统，对你工作的安全大大加强。-simple file encryption code a good file encryption system, you have the right security greatly enhanced.

JAVA通用类处理(BASE64)-JAVA generic class treatment (BASE64)

WTLS安全层源程序-WTLS layer security source

它也可以用来解除Adobe Acrobat PDF文件密码的工具，它可以帮助解决加密PDF无法编辑和复制/打印的问题，支持所有版本的Acrobat加密(包含7.x)，也支持128位加密。 -It also can be used to lift the Adobe Acrobat PDF files password tool, it can help to solve encrypted PDF can not edit and copy/print the questions, and support all versions of Acrobat encryption (including 7.x), also supports 128-bit encryption.

vb写的DES源码，复制到Visual Basic 6.0 中即可使用。-vb source code written by DES, copy to the Visual Basic 6.0, can be used.

What Does the code DO? Sometimes we may desire to hide our file contents from others.One of the possible way is encrypting these files.Here a simple encryption technique is used(In VB - The same technique can be implemented in "c" also.) Program flow Explained * Open the File to be encrypted for Binary Access Read(Say Source File) * Open a temparory file where encrypted data is stored for Binary Access Write(Say Destination File) * Loop through the Source File Byte by Byte * For each byte read from the file, Complement the data. (Using Not operator (in C we have to use "~" operator) * Write Complemented Data to Destination File * Delete the Source File * Rename Destination file as Source File(Now Encryption is over) -What Does the code DO? Sometimes we may desire to hide our file contents from others.One of the possible way is encrypting these files.Here a simple encryption technique is used (In VB- The same technique can be implemented in

数据加密的一个库：Crypto++，功能很多，接口完善。-A data encryption library: Crypto++, Features a lot of perfect interfaces.