Playfair Cipher 1.not even the large number of keys in a monoalphabetic cipher provides security 2.one approach to improving security was to encrypt multiple letters 3.the Playfair Cipher is an example 4.invented by Charles Wheatstone in 1854

一系列的加密算法，包括恺撒密码、KeyWord密码、PlayFair密码、Vigenere密码、LFSR密码、RC4密码、DES密码和IDEA密码。-A series of encryption algorithms, including Caesar password, keyword password, the Playfair password, the Vigenere Password, the LFSR password, RC4 password DES password and

The Vigenère cipher is a method of encrypting alphabetic text by using a series of different Caesar ciphers based on the letters of a keyword.

加密解密的一般性算法，C++代码，windows平台，visual studio 2016编写-visual studio 2016