密码术(二) 转自推理之门

密码表1 Q W E R T Y U I O P A S D F G H K J L Z X C V B N M
密码表2 E K P R J B D N C V O U H T Y W Z X M L A S F I G Q
第一个密码表加密第一个字母，第二个密码表加密第二个字母，第一个密码表又
extended up in the air] stood for E. As you are aware, E is the most
common letter in the English alphabet, and it predominates to so marked
an extent that even in a short sentence one would expect to find it
most often. Out of fifteen symbols in the first message, four were the
same, so it was reasonable to set this down as E. It is true that in
some cases the figure was bearing a flag, and in some cases not but it
R X B A G U C D M K U I L U M S I L D I U L D G A B P C B U C C A K M H
V O X M U R A X B Y U G U M Y H X P R X M A I L U M Y P M P R P D C B X
O H X P O M X I A W X X S I L O A A B X O I H U R X P O I O D U M D M K
was an invitation which he would not refuse, since he could never
imagine that it could come from anyone but the lady. And so, my dear
Watson, we have ended by turning the dancing men to good when they
UO EMN QUD
2.U B H X P P R A I L A F X K A E L U F L U L D G A A N V C D U M A K R
D U K L X C M A R H X P E U C C B U M K I L D I U I R U M V C H M A D M
密码术（二） 转自推理之门
现放出上篇的练习：
1.MQPUOZ WOLN DNLWZOUVNG MWFNPND EMQE EMN YXATWSY YEWWG HWD SNEENDY QOG
MQPUOZ QIISUNG EMN DCSNY FMULM ZCUGN CY UO QSS HWDAY WH YNLDNE FDUEUOZY
起的作用并不大，聪明的破译师仍然能在里面找到许许多多破译密码的线索。直
到有一天，佛罗伦萨的里昂巴蒂斯特·阿尔伯提提出了一种多字母替换密码，即
是用两个或两个以上的密码表交替使用来进行加密，如：
明码表 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Baker Street for dinner."
明码表 A B C D E F G H I K L M N O P R S T U V W X Y
密码表 D W F K A B Y L U S C M M X V O R I P G E N H
解答者：hoon
（这篇的难点是M既替换N，又是本身，这是后来一些编码师用来迷惑破译者而设
2.Q的后面多是U；
3.当一个单词知道其中大部分字母后，不妨查查英文字典（当然，很懂E文的就不
用了～～～），如果字典里只有一个单词符合条件时，就会很快的知道其他字母。
上面的只是抛砖引玉，希望大家有什么好方法也告诉一下～～～
解密或许是个沉闷的过程，但当你找到解法后，又会很兴奋，大家ENJOY一下吧！
have so often been the agents of evil, and I think that I have
fulfilled my promise of giving you something unusual for your
notebook. Three-forty is our train, and I fancy we should be back in
2 C D E F G H I J K L M N O P Q R S T U V W X Y Z A B
3 D E F G H I J K L M N O P Q R S T U V W X Y Z A B C
4 E F G H I J K L M N O P Q R S T U V W X Y Z A B C D
明天休息，后天再更新吧，偷懒中～～～
to be continued......
先给出上篇的答案吧：
1."Having once recognized, however, that the symbols stood for letters,
and having applied the rules which guide us in all forms of secret
A B O X M D M H X M A W P I I L A C D K H D M K R X M H K A D O E D I R
X M E A L D G A A M K A K W H I P O M U M Y I L A K D M F U M Y M A M I
X Y X X K E L A M I L A H L D G A R X X B I A M W A A M I L A D Y A M I
了。经过几个人的努力，最后，维热纳尔终于将其完善了。他编出了一个系统而
有效的密码。那就是维热纳尔密码，其主要构成是维热纳尔方阵：
a b c d e f g h i j k l m n o p q r s t u v w x y z
1 B C D E F G H I J K L M N O P Q R S T U V W X Y Z A
加密第三个字母，不断地重复......那么：
明文 F O R E S T
密文 Y Y J J L L
这样，按原来的方法进行频率分析就没有什么作用了。这只是两个密码表时的情
况，如果用三个，四个或以上的密码表后，破译就显得非常非常困难。即使是这
样，阿尔伯提未能把他的理念发展成一个完整的系统。这个任务当然由后人完成
both arms extended up in the air]
明码表 A B C D E F G H I J K L M N O P R S T U V W X Y
密码表 Q T U G N H Z M U R B S A O W I D Y E C P F K X
解答者：drhorse，菩提
was probable, from the way in which the flags were distributed, that
they were used to break the sentence up into words. I accepted this as
a hypothesis, and noted that E was represented by [the stickman with
HDWA EMN FQX UO FMULM EMN HSQZY FNDN GUYEDUTCENG EMQE EMNX FNDN CYNG EW
TDNQB EMN YNOENOLN CI UOEW FWDGY U QLLNIENG EMUY QY Q MXIWEMNYUY QOG
OWENG EMQE N FQY DNIDNYNOENG TX EMN YEULBAQO FUEM TWEM QDAY NKENOGNG CI
R F X M A L A O A D I X M F A U E D R F X M G U M F A K I L D I U I E D
R D M U M G U I D I U X M E L U F L L A E X P C K M X I O A B P R A R U
M F A L A F X P C K M A G A O U M D Y U M A I L D I U I F 字母替换密码完全失去了效用。因此，密码编码者想
方设法去编一种更强大的密码。一些编码者对单字母替换密码做了一些改动，如
在编码过程中，加入一些特殊的字符，或者令一些字母不代表另一个字母，而是
代表一种程式，譬如是代表空格，代表删去前一个字母，代表换行等。但这一切
HUHENNO YXATWSY UO EMN HUDYE ANYYQZN HWCD FNDN EMN YQAN YW UE FQY
DNQYWOQTSN EW YNE EMUY GWFO QY N UE UY EDCN EMQE UO YWAN LQYNY EMN
HUZCDN FQY TNQDUOZ Q HSQZ QOG UO YWAN LQYNY OWE TCE UE FQY IDWTQTSN
（这篇的难点是E以特殊的形式出现，令单字母单词有三个）
2."If you use the code which I have explained," said Holmes, "you will