Reply To: Puzzles
This contains the solution to my Meta puzzle.
[SOLUTION]
The instructions were encrypted with a ROT13 cipher (i.e. Caesar shift of 13). The decrypted instructions are:
- Read these instructions carefully!
- Each of the four feeder answers should have exactly 16 characters (using Latin letters only).
- Derive a 64-letter keystream, K, from these answers as follows.
- Have you got Answer A? If so, the 16 letters from this answer should make up the 1st,5th,…,61st letters of K (in that order!).
- Easy. Now use Answer B to create the 2nd,6th,…,62nd letters of K.
- Repeat for Answer C (3rd,…,63rd letters of K).
- Repeat for Answer D (4th,…,64th letters of K).
- If you are confused with which answer is which, a look at the titles may help!
- Now decrypt the following message, using K as a one-time pad.
- Good luck!
Here are the feeder answers that the instructions refer to. Note that, for instance, Answer A is the solution to Annoying Answers (because both letters of the title begin with A).
A. CRYPTOGRAPHYWINS
B. GOODLUCKEVERYONE
C. WILLYOUSOLVETHEM
D. SOMETOUGHPUZZLES
Which yields a key K as listed in the instructions. Taking Z-K, where Z is the ciphertext, yields a plaintext P:
Z: YNEUYCJXCQEMESPEKDGGHBSHOVFYFPLNEROAXJYPSGDJFVVBDYEKMBNPGUMWQIMJ
K: CGWSROIOYOLMPDLETLYTOUOOGCUURKSGAEOHPVLPHEVUYREZWYTZIOHLNNEESEMS
P: WHICHOBJECTAPPEARSINTHETITLEOFTHENATIONALCIPHERCHALLENGETHISYEAR
Or:
Which object appears in the title of the National Cipher Challenge this year?
The answer is: THE SILVER BULLET