古典密码课设。C++ 多表古典加密方法主要有Playfair体制、Vigenere体制、Beaufor体制、Vernam体制和Hill体制，用高级语言实现其中一种体制的加密和解密算法。 -Classical cryptography class-based. C++ multi-table classical encryption methods Playfair system, Vigenere system, Beaufor system, Vernam system and Hill