classicalcryptography

代码说明：

  古典密码算法 　　通过编程实现替代密码算法和置换密码算法，加深对古典密码体系的了解，为以后深入学习密码学奠定基础。(Classical cryptographic algorithm By programming a substitution cipher algorithm and permutation cipher algorithm, a better understanding of classical cryptography, cryptology for the future lay the foundation for further learning.)