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Break the code

  1. Jan 15, 2007 #1
    I feel justified in making a reusable thread because it is unique to this section. Here's my idea. I take a few sentences or words that make sense and apply simple coding techniques and if anyone cracks it, I move onto the next one. I will not be posting any hints and will not move onto the next question until the message is found.

    In general I will stick to trivial methods of coding messages, and will not do anything too complex(no use of foreign languages or anything dumb like that). All solutions are full sentences that make gramatical sense and are formed using common english words.

    You may publicly discuss any thoughts or ideas you have on any of the messages in the hopes of solving it collectively, if you wish. There is no need to use coloured text.

    Here is the first one:

    Can you make sense of this?

    ENOREJSIHNADNAR
    VLISEEPOMIEHTEG
    HTOTNHTSEROTDES
    IMEHTAENENOLCSK
    KNISDOEHTWRAHSO
    NASWAASEHSWTEHT
     
    Last edited: Jan 16, 2007
  2. jcsd
  3. Jan 16, 2007 #2
    Are these seperate seperate words or is this a complete sentence?
     
  4. Jan 16, 2007 #3
    They will all be complete sentences. (So, yea, it's a complete sentence.)
     
  5. Jan 16, 2007 #4
    It looks similar to problems I've seen where you sort of wind a sentence into a grid. So if you know the magical starting location, you can work your way horizontally, diagonally, and vertically towards the answer. But I don't see an obvious starting location, and I'm not sure I'd have the patience assuming that it's even the right method. Cuz, if it's wrong, I've just wasted a lot of time!

    Otherwise, we can assume that these are very positionally important from top-to-bottom as well as left-to-right, as evidenced by the fact that you used a fixed-width font. If it was a normal cypher or jumble, you probably wouldn't have bothered.

    Given the letter distribution, I'd guess it hasn't been encoded with any sort of letter-by-letter system. Probably the letters are all accurate, but moved around.

    Could be that it was laid out in lines (as normally), but then each row/column was shifted one-at-a-time in a certain order, yielding the result. But again, difficult to tell. Oh, and even more difficult if there's any extraneous characters!

    I had one I liked a while ago that did some scrambling. Here's 3 examples all scrambled the same way:

    ITNRCYGASREATEBSHOARRSRETHRAMLTMTNKSEPOHLEOIRAOHPEGMMLEW
    UTIHABMSEKSARWTCMEATAESRESMTRELDSEDGIMHHB
    SPCAWEITCIEAAINTNEILHTNELPTNCILYOISCLZPONMLKIAUTGUIOAATUDNE

    Very difficult to hack, even when you know how to unscramble it!

    DaveE
     
  6. Jan 16, 2007 #5
    Interesting... The PF software seems to want to insert spaces into them when displayed as HTML, but not when editing the messages? Huh. Right at the 50th character both times.

    DaveE
     
  7. Jan 16, 2007 #6
    I think its called a Vigenere square or Vigenere Cipher.
     
  8. Jan 16, 2007 #7
    Huh, this worked pretty well!


    PHCIGI
    YEATSL
    DICNOE
    UULTXM
    RSPEEF
    TIFNRD


    DaveE
     
  9. Jan 16, 2007 #8
    I want to give hints... but then on the other hand, I don't. We'll see if this is solved next week, if it is not, I MIGHT post a hint.

    Do note that I wouldn't make it that hard though, because I want these to be fun, not a "can I see if I can make it so hard that noone can do it" kinda fun, either. :-)

    You definitely will not have to be a member of the NSA to crack my codes/scrambles/whatever.
     
    Last edited: Jan 16, 2007
  10. Jan 18, 2007 #9
    Ok hint : Can you see any words that make sense? Can you start to develop the sentence from that point?
     
  11. Jan 18, 2007 #10

    Gokul43201

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    Gold Member

    It's clearly not a substitution cipher. Looks like a transposition, and from your hint above, it's not a permutation - I'd guess it's probably a route or columnar transposition. Too lazy to do any more than that...but someone else can take it from here.
     
  12. Jan 18, 2007 #11

    radou

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    Homework Helper

    I see the word 'see'. :biggrin:

    Caesar's code perhaps? Will look at it later.
     
  13. Jan 18, 2007 #12
    Yes, frequency analysis suggests this is monoalphabetic and is not a substitution[1]

    Looking at the grouping:

    Row: 15 chars
    Column: 6 chars

    3 is a common factor so a good candidate for transposition.

    Code (Text):

    ENO REJ SIH NAD NAR
    VLI SEE POM IEH TEG
    HTO TNH TSE ROT DES
    IME HTA ENE NOL CSK
    KNI SDO EHT WRA HSO
    NAS WAA SEH SWT EHT
     
    Note the bottom right and top left words are reverals of THE and ONE, there are a few 3 letter words. Could be something...
     
    Last edited: Jan 18, 2007
  14. Jan 18, 2007 #13
    Problem is, I can do it too often.

    "Greeks halt the rest", "I spose I rot", "See the TV", "Does he test hens?" And I'm sure I could find lots more. If it's a sentence wound around in a box, I can start in lots of places and get lost. I can spend a few minutes on a particular starting point, get stuck, and then STILL try the same starting point differently a few times before I move on. Although, I think I might rule out the "sentence wound around in a box" idea, since I can't seem to find a good word for "V" other than "TV".

    The one I was referring to before where I made a simple square illustrates a little bit of the difficulty in knowing the pattern. Here's how I did that one:

    "Suprisingly more difficult than expected"
    Changed to upper case, and removed the spaces, giving us a 36-character string, written in a 6x6 box:

    SUPRIS
    INGLYM
    OREDIF
    FICULT
    THANEX
    PECTED


    First move the letters in the first row to the right by 1 square, and any that wrap around, move to the front:

    SSUPRI
    INGLYM
    OREDIF
    FICULT
    THANEX
    PECTED


    Next, move the 1st column down by 1 square:

    PSUPRI
    SNGLYM
    IREDIF
    OICULT
    FHANEX
    TECTED


    Now, move the 2nd row over to the right by 2 squares:

    PSUPRI
    YMSNGL
    IREDIF
    OICULT
    FHANEX
    TECTED


    And next (you guessed it) move the 2nd column down by 2 squares:

    PHUPRI
    YESNGL
    IRSDIF
    OMCULT
    FRANEX
    TICTED


    Repeat until you get:

    PHCIGI
    YEATSL
    DICNOE
    UULTXM
    RSPEEF
    TIFNRD


    I didn't think it would actually yield such confusing results-- I thought there would be more patterns in it. As is, there seems to be only one ugly one, which is that the diagonal from upper left to lower right is the last letters of the sentence in order. There's a few other small patterns, but nothing very significant.

    Anyway, after I noticed that, I figured that given the amount of crazy ways to shift things around in a pattern like that, this puzzle would take WAY too long to solve it.

    DaveE
     
  15. Jan 18, 2007 #14

    Gokul43201

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    Gold Member

    Caesar's code is a substitution cipher - this doesn't appear to be. Also, this wouldn't be a scytale cipher, owing to the hint. The hint strongly suggests a route cipher, with a non-random (i.e., a recognizable) route. There may be dummy characters (to fill out the box) that account for the difficulty with the V pointed out by davee.

    I've neither seen, nor thought about ways to attack transpositions. Very likely, warren has a trick up his sleeve for just this kind of thing.
     
    Last edited: Jan 18, 2007
  16. Jan 18, 2007 #15
    I see something in my original post that should not be there. The solution is NOT a full sentence. Although from the looks of it, this has not affected anyone's answer or endeavor yet, but I want to ensure that I make that clear. It is almost a full sentence and makes perfect grammatical sense. I don't really think that the fact that it is not a full sentence matters, but I just wanted to point it out.

    I think it is true that this is harder than I thought it would be. I am unsure as to whether or not to continue this thread after this one is done, but I am very confident that this one can be solved. You guys are close!
     
    Last edited: Jan 18, 2007
  17. Jan 19, 2007 #16
    Ok I think it is appropriate to close this thread now. I want to thank everyone who tried for trying! I was hoping that it would work but I think that the majority of you are correct, it is just too damned hard. When I saw 3trQN's idea I was thinking that it was only a few hours away from being solved, but I don't think so.

    So anyways, yea, thanks everyone for trying, I appreciate it. Here is the solution, discolored for those who don't want to see it yet.

    >>You were all correct when you said it was a column cipher. Since there are 15 rows, in order for the columns to be seperated evenly, they must be seperated in either 5 columns of 3 or 3 columns of 5. It was 3 columns of 5.



    ENORE JSIHN ADNAR
    VLISE EPOMI EHTEG
    HTOTN HTSER OTDES
    IMEHT AENEN OLCSK
    KNISD OEHTW RAHSO
    NASWA ASEHS WTEHT


    Then just read it backwards from the bottom right to the top left.

    <<<<<
     
    Last edited: Jan 19, 2007
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