WATAE TXLAL PDIBI MGTBU YBTMM FJBJW KBEIZ SGLZQ CCOCT XMQHM QSLFS
AOBFX QQRCK CJSME XFHLT GYSJN QEQUM FNPIZ ZMCWE PXQOD UIDLO SXLCV
CGIWI UIVYC HLYAE TKYKY RVOVZ FJWAR RCYCN SSJNN ADVZB BMQJQ UVGKC
UCPVN BGRZA EVOMF THBSK OZUYQ QDGUO FUIAT XOWPN QESJM MUHHU XBTMM
NYGYF YFNFH VIATB UOHPD QVJAT AEYLT MQTLE EXBTH MMYCT BDDAX

Determine what this cipher says, and the method of encryption, using the following hints:

• It is not a simple substitution cipher.
• Both the original plain text message and the encrypted message contain 270 characters (maybe with meaningless filler characters at the end).
• Only one rather simple method of encryption has been used.
• The encryption method is fairly robust. In other words, an error (while encrypting or decrypting) does not scramble the entire remaining message. Some very complicated ciphers have this problem.
• In the encrypted text, M and T appear most often, and R appears least often (I do not think these facts help at all).
• Both the original plain text and the encrypted message read from left to right.
• You might be able to guess the full text after determining only the first three words.

Even though I know what the first part of the message is (I haven't memorized the constitution), I still don't know how to get to this message. On inspecting the message and code, it seems that there are many letters in common.

PGKKW XIMAF TNEGA NFYGZ TMUIV
PREAM BLETO THECO NSTIT UTION

WATAE TXLAL PDIBI MGTBU YBTMM
WETHE PEOPL EOFTH EUNIT EDSTA

Out of those 50 letters I compared, 8 were the same in both lines. That's more than it should be if it were left up to chance.

Also, if you look at the fourth word of the decrypted title and the decrypted message, they both end in "IT." Even though "IT" is in the same place for the two codes, it is encrypted to "GZ" in the title and "BU" in the message. This proves (unless I have the title wrong) that the letter and position are not the only factors in decrypting.

I hope that some one else comes in and shows me how obvious it is and that it was right in front of me.

Posted by Tristan on 2003-12-09 20:19:57