c++的MD5类，简单好用，只需要包含进去，就能方便使用

为一个字节或字符数组或串计算md5值，内部只创建一个数组，节省分配时间，节省内存 完全是static方法，线程安全 注意对返回值的处理，见注释-for a byte array or character string or md5 value calculation, only to create an internal array, saving time allocated to save memory is completely static method, thread-safe attention to the return value, see note

java编写MD5加密生成例子，对于需要加入密码验证的程序绝对实用，可以进行直接拷贝使用。-prepared MD5 encryption generated example, the need for password verification procedures for the practical, direct copy.

算术运算实现字母的替换。凯撒加密就是一种单字母替换法：通过用户给出密钥将字母加上密码变成密文-Arithmetic operations to achieve the replacement of letters. Caesar encryption is the replacement of a single-letter law: the user is given the letter key will be encrypted into a ciphertext

用VC编写的一个简单的文件加密的程序源代码-VC prepared by a simple document encryption source code

DES加密算法的实现和演示，具体算法见网上，程序中有注释-DES encryption algorithm and demonstrate the achievement of the specific algorithm see online, proceedings have Notes

DES算法的标准-DES algorithm standard

这是一个混合密码系统，利用多种方式加密-This is a mixed-code system and a variety of forms of encryption

我用C#做的一个对字符串加密的程序，加密对象为26个字母大小写和0到9的数字，实现的是替代法-I used C# do a strings encryption procedures, encryption targeted at 26 case-sensitive alphanumeric 0-9 and figures to achieve the substitution

密码学文献有一个奇妙的发展历程，当然，密而不宣总是扮演主要角色。第一次世界大战前，重要的密码学进展很少出现在公开文献中，但该领域却和其它专业学科一样向前发展。-cryptography literature has a wonderful history, of course, close does not declare always played the leading role. Before the First World War, it was important to cryptography little progress emerged in the open literature. However, the area has other professional disciplines and the development of the same.

加密、安全、压缩处理，实例，有爱好者可以学习-Encryption, security, compression treatment, examples have lovers can learn