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You are a spy trying to find out the job of a man named John. One day, you go up to John's friend, Joe. You tell Joe that if he doesn't tell you what John's job is, you will destroy him. Not wanting to die, Joe says "OK", but there is one rule - decode this message, and you will find his job. You are given a sheet marked 'Table' that reads the following:

[79] [D8] [1B] [3A] [22]
[P9] [22] [24] [ZP] [21]
[31] [P9] [60] [33] [1C]
[D0] [43] [43] [21] [27]

He then gives you another sheet marked 'Path', which reads as follows:

74,74,74-72,6B-74,74-72,6B-74-6B,6B,6B,6B-72,75,74,74,72-74

What is John's job?

Hint 1:

Uri worked out the path. I'm now going to give you a clue as to what the path means. The path actually tells you how to move about the table. So, 'l' is 'move left', 'r' is move right, 'u' move up and 'd' move down. Now you just have to decipher the table...

Hint 2:

The table is encrypted by converting letters to their respective hex code. This hex code is what a PS/2 keyboard sends to a computer. The computer then decrypts it, and turns it into a nice strong of letters. Come on, this is a BIG hint, so hopefully now someone will get it. If not, I'll be adding another hint soon!

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    $\begingroup$ sounds to me like Joe isn't so scared of being destroyed! haha $\endgroup$ – JLee Mar 16 '15 at 19:08
  • $\begingroup$ @JLee - Yeah, I had quite some trouble think up a storyline. Best I could come up with! $\endgroup$ – user9377 Mar 16 '15 at 19:17
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    $\begingroup$ @Kslkgh: I converted 6B, 72, etc. to their ASCII symbols. $\endgroup$ – Joe Z. Mar 16 '15 at 19:33
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    $\begingroup$ rrr-dl-rr-dl-r-llll-durrd-r? $\endgroup$ – Uri Granta Mar 17 '15 at 8:24
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    $\begingroup$ + tag 'steganography' on basis of OP's comment "the table also contains a lot of junk that means absolutely nothing". $\endgroup$ – A E Mar 18 '15 at 10:28
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Thanks to the BIG hint, John's job is:

a mechanic. The path encoding uses hex scan codes for a PS/2 keyboard so path directions use the arrow keys: left=6B, down=72, right=74, up=75

As identified by Uri, the path through the table is 3A, 24, 21, 33, 1C, 31, 43, 21 which decodes to MECHANIC. Here is the path and table:

Table

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  • $\begingroup$ You are right in your thinking that the path could be Base-16. It is. However, the table is also in Base-16, but a lot of it is actually random jumble inserted by me to confuse anyone trying to work out these. Both the table and the path are in hexadecimal, but the table also containf a lot of junk that means absolutely nothing. $\endgroup$ – user9377 Mar 17 '15 at 7:38
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    $\begingroup$ You got it, Len! I'll be uploading another cryptogram soon! $\endgroup$ – user9377 Mar 19 '15 at 8:00
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    $\begingroup$ Congratulations! Also, nice diagrams! $\endgroup$ – Uri Granta Mar 19 '15 at 8:19
  • $\begingroup$ @Len - I know you've been waiting (and dreading the moment)! Here it is! $\endgroup$ – user9377 Jun 20 '15 at 15:49
  • $\begingroup$ @Len The latest is here $\endgroup$ – user9377 Jun 28 '15 at 7:01
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Here's an explanation of my progress so far.

Path

1. Four unique strings suggests a sequence of compass directions (udrl/nsew) to help us pick out characters in the grid.
2. There are 7 hyphens and 12 commas, suggesting that letters are separated by the former rather than the latter.
3. Starting at the top-left edge, there is only one way to interpret the directions such that we stay within the grid throughout: 74 must be right (since there are 5 of these with at most one reverse between them), 6B must be left (since there are 4 in a row), 72 must be down and 75 must be up.
4. The path is therefore: rrr-dl-rr-dl-r-llll-durrd-r.

But why? Interpreting the values as hex (see @Len's answer) we get L=106, D=114, R=116, U=117 (or possibly WSEN). This is clearly not ASCII or any other lexicographic encoding (including mod-26). Neither does it correspond to the qwerty or dvorak keyboard layouts, or character positions in the question itself (with or without punctuation). The fact that one value is far from the others implies that the encoding is connected with the letters rather than the meaning of the letters (e.g. arrows). A potentially useful hint from question comments is: "It's not ASCII, it's a different set of computer codes"

Table

1. The path above gives us the eight character word 3A-24-21-33-1C-31-43-21
2. Interpreting the values as hex we get 58-36-33-51-28-49-67-15.

The range of these values is 52, so again is unlikely to be lexicographic; @Len has also checked shifted mod-26 and shifted absolute diffs. The numbers lie in two ranges plus two outliers: 28-36, 49-58, 67 and 15. One or both of the outliers could be punctuation.

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  • $\begingroup$ Very nice progress ;-) $\endgroup$ – Len Mar 17 '15 at 16:29

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