说明：  Polybios密码体制： 如下图所示，加密算法的规则是明文中的每个字母都用字母所在的行和列的字母代替。当然表中的字母可以换。
(Cryptosystem Polybios: As shown below, encryption algorithm is expressly rules of each letter are letters where rows and columns to replace the letters. Of course, the table can change the letters.)