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Ciphers and Puzzles from Competitors

Viewing 15 posts - 1 through 15 (of 268 total)
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  • #45711
    10degrees-admin
    Keymaster

    Let’s start a thread for competitors’ ciphers.

    [Good idea, here are the rules:

    If you want to set a puzzle or quiz question post it together with the answer putting the answer in square brackets with ANSWER PLEASE DO NOT POST THIS BIT at the start. For example:

    What is 2+2

    [ANSWER PLEASE DO NOT POST THIS BIT

    4

    ]

    (I know this is not a good puzzle, OR a good quiz question, but what do you expect?)

    We will start easy (maybe not that easy) and work up as the competition goes on so that everyone has a good chance to solve your challenges.

    Same idea for ciphers. If you would like to challenge the gang post the challenge together with the decrypt and a quick description of how it was encrypted. We might not post those, especially at the start, but we will certainly look at them.

    Harry]

    #45886
    Inactive

    Harry, no matter there difficulty it may be better to put some up on day one as fillers during the ‘easy’ NCC challenges, there may be less time for them in the later stages. What do think?

    #45901
    Harry
    Keymaster

    I think that is an excellent idea, and in fact we may have a really nice surprise in a couple of days. In the meantime we will publish competitor challenges as long as they are submitted in the format I suggested above [Hint, hint]
    Harry

    #45950
    Inactive

    @Harry Sorry about the double posting

    [I didn’t see the second post,The-Letter-Wriggler are you sure there was one? Harry]

    #45722
    Inactive

    WILL YOU BE THE FIRST TO SOLVE THIS?

    TITLE – TLW CIPHER:
    ——————————————–
    Yet To Solve ThiS One
    tHe hIntS
    eVery LIne Will EacH
    ONLy BE a LittLE Twisted
    ——————————————–

    All posts to go below and kept in this thread please.

    When you have solved it choose any 6 non consecutive letters from the plaintext, retain their order from left to right, and post them without spaces as your answer.
    Do not use the same 6 letters as other posts.

    Your post to look like this: TLW Answer: ABCDEF

    The first competitor to post the CORRECT answer gets all the glory.
    Of course all other correct posts will be deemed very worthy too.

    #45968
    Harry
    Keymaster

    The-Letter_Wriggler’s puzzle above is impossible, but very clever! Don’t worry if you can’t get it, there will be easier ones coming soon from a special guest!

    Harry

    #45991
    10degrees-admin
    Keymaster

    No, not impossible.
    TLW: OLTEET

    #45996
    Harry
    Keymaster

    I might have to put you guys on a separate site!

    #46005
    Inactive

    Before I could comment you Harry, Madness does it for me.

    So Madness of course gets all the GLORY as I expected he would!

    That was one fast solve my friend.

    I now await all the worthy contestants.

    #46392
    Inactive

    Harry is there a way of keeping this thread at the top of the forum?
    It will go out of sight without any posts being made.
    Think — Out of Sight – Out of Mind —

    #46395
    Harry
    Keymaster

    Done!

    Harry

    #46598
    10degrees-admin
    Keymaster

    Today’s episode is brought to you by the number 7197738.

    This is actually an encoding rather than a cipher. It was inspired by an on-line challenge at
    https://susec.tf/tasks/gantun_229621efd1dcc01ef8851254affd1326887ec58e.txz

    I took their algorithm and reduced to to only use the letters A-Z. Here is the Python code that I used to encode the “ciphertext”. Because indentation is important in Python, and because the forum server removes spaces from the beginning of every line, you should replace every occurrence of “[INDENT]” with 8 spaces (or a tab) in the following code before you use it.

    from random import randint
    alphabet = “ABCDEFGHIJKLMNOPQRSTUVWXYZ”
    def encrypt(p):
    [INDENT]numbers = []
    [INDENT]for char in p.upper():
    [INDENT][INDENT]numbers.append(alphabet.index(char)+26)
    [INDENT]while len(numbers) > 1:
    [INDENT][INDENT]n = randint(0,len(numbers)-2)
    [INDENT][INDENT]x = numbers[n]
    [INDENT][INDENT]y = numbers[n+1]
    [INDENT][INDENT]if x > y:
    [INDENT][INDENT][INDENT]z = x*x + x + y
    [INDENT][INDENT]else:
    [INDENT][INDENT][INDENT]z = y*y + x
    [INDENT][INDENT]numbers = numbers[:n] + [z] + numbers[n+2:]
    [INDENT]return numbers[0]

    Here is the “ciphertext”:

    106383886716898490132849808893959579644966513504668004893376273104567230060478853561821154300405528376830349480440305515628682136413218581984172008217451482183624183648735550855010971762114675826856238674946359430

    If you enjoy this sort of thing, I have another one ready, called the “factorization cipher”. Yes, I stole it too from somewhere else.

    [I should note that I had to do a bit of tinkering to make the code run – mostly because some of the characters rendered on the website are not recognised by Python. Try retyping offending lines if you can’t tell what the problem is! Also, nice job on [INDENT] being exactly eight characters.

    water_biscuit]

    #46690
    Inactive

    Should EACH [INDENT] be only 4 spaces? I get error with 8. (using Thonney)
    If using paste the quote marks will need to be replaced as they are ‘web’ quotes.

    #46761
    10degrees-admin
    Keymaster

    Each [INDENT] should be exactly the same as every other [INDENT].
    I don’t know who Thonney is, but you should kick him to the curb.
    The corruption of ‘ and ” is due to the server. It does that to everything.

    #46792
    Inactive

    @Madness Hi there 🙂
    Thonney is simply a windows based interface to run the standard and current up to date python, it has nothing to do with the actual programming of python.
    I was simply asking not stating about the indentation. I replaced each [INDENT] with 4 spaces and it looks and works fine.
    You know from my emails to you that I have just started to learn the python instruction set as I program in Pascal, I am not new to programming.
    Agree with the corruption statement, I was just pointing it out for others.

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