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#61 dawh

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Posted 28 October 2010 - 09:53 PM

Hooray for octopuppy! Showing you are the true Evil Mastermind.

Here's a question resulting from my attempted code development: What's the requirement for having to remember all the steps in the code? You've established that since you cant see the password characters after you've entered them, the remaining letters shouldn't depend too much on what was already entered (for those of us with short memories). But in this hash, there may be an implementation problem in remembering which rules to apply to which characters of the password (eg, does the munber of vowels become the third character or the fourth?).

Octopuppy's original code had some elegance that later ones have lacked: That the same basic rules are applied throughout the construction of the password. Code #2 mixed that up a bit, but at least repeated the same requirements for the first 4 characters and the last 4. Code #3 has essentially 8 independent requirements. The one I've been trying to construct does also, but I've found when trying to apply it I have to look back at my cheat sheet to know what to do next, which is not in keeping with the spirit of the game.

Thoughts?

I agree. Araver's algorithm was pretty clever and certainly did a pretty good job at obfuscating, but it did seem like it would be a pain to calculate each character (especially the whole last prime position thing). I've developed an algorithm that's more in keeping with octopuppy's original method. I think that it's fairly easy to do in your head, though I admit that I wrote up a program to crunch the numbers (er, letters) faster. I'm actually glad I did because I caught an error in one of the ones I did by hand when I was developing it... :P

In any case, I didn't need a cheat sheet for my method and I only figured programming it would be faster because I have always been really slow at calculating anything in my head. :rolleyes: I'm much faster when I can see it.
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#62 araver

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Posted 28 October 2010 - 10:31 PM

:rolleyes:

OK, I admit, I had a hard time learning the algorithm also. You don't get 40s the first time, you need training :ph34r:

Maybe silly children songs could work:
Spoiler for Repeat after me:

I admit I don't have much talent, but it could be turned into a mnemonic ...

It's at least plausible, right? :rolleyes:
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#63 octopuppy

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Posted 28 October 2010 - 10:43 PM

I agree. Araver's algorithm was pretty clever and certainly did a pretty good job at obfuscating, but it did seem like it would be a pain to calculate each character (especially the whole last prime position thing). I've developed an algorithm that's more in keeping with octopuppy's original method. I think that it's fairly easy to do in your head, though I admit that I wrote up a program to crunch the numbers (er, letters) faster. I'm actually glad I did because I caught an error in one of the ones I did by hand when I was developing it... :P

In any case, I didn't need a cheat sheet for my method and I only figured programming it would be faster because I have always been really slow at calculating anything in my head. :rolleyes: I'm much faster when I can see it.

I think writing a program or something of the sort is highly advisable. I used a spreadsheet to calculate the hashes for the two I did. I did them manually too, to check I could get it in the time limit, but posted the spreadsheet-done versions to avoid mistakes. It saves time, otherwise you have to obsess over them to make sure they are right.

Hooray for octopuppy! Showing you are the true Evil Mastermind.

Aw shucks :blush:

Here's a question resulting from my attempted code development: What's the requirement for having to remember all the steps in the code? You've established that since you cant see the password characters after you've entered them, the remaining letters shouldn't depend too much on what was already entered (for those of us with short memories). But in this hash, there may be an implementation problem in remembering which rules to apply to which characters of the password (eg, does the munber of vowels become the third character or the fourth?)... Thoughts?

I think it's your call really. Personally, I try to bear in mind what I would want to use in real life, so I don't go overboard with the complications. My second code, although it had more rules, also had a pattern to help me remember what to do, but I don't want to impose that style on anyone else, it's more fun to see what you come up with. Your limitation is the rule not to have to memorise an excessive amount of information, but it's up to you to decide how much is too much. I do feel that in some sense a more elegant algorithm is a better one, but a less elegant algorithm may make up for that in other ways.
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#64 octopuppy

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Posted 28 October 2010 - 11:13 PM

:rolleyes:

OK, I admit, I had a hard time learning the algorithm also. You don't get 40s the first time, you need training :ph34r:

Maybe silly children songs could work:

Spoiler for Repeat after me:

I admit I don't have much talent, but it could be turned into a mnemonic ...

It's at least plausible, right? :rolleyes:

On the subject of mnemonics, rule 3 forbids what I think is the most effective technique you can use, which is to have an alphabetic substitution table.

Handy technique for that:

Try to come up with 26 really easy to remember words, like
Apple
Bear
Cow
and so on, but particularly try to pick things which can have a very vivid and simple mental image.
Also try to superimpose the initial letter on the mental image so you associate "A" with apple. See the shine on that apple. Look how juicy and fresh it is.
Then when you see an "A" you think apple and know that "A" maps to "E" (last letter)
"B" maps to "R"
"C" maps to "W"
etc.
Now you have an alphabetic substitution table memorised. Try it, it's easy!
If you want to be fancy about it, try to pick 26 words so the last letters also span the alphabet (worth doing, now you can also use it for encryption)
If you want to be really fancy, try and do it so that repeat operations (A -> Apple -> E -> Egg -> G -> Goat -> T) go round the entire alphabet. There's probably a name for that sort of permutation but I don't know what it is.

Anyway, if you want a hash to use in real life, incorporating the use of something like that will make it hard as nails. A straight letter-by-letter substitution is still breakable, but complicate it in some minor way and it's really difficult to break.
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#65 araver

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Posted 31 October 2010 - 12:41 AM

So, CherryLane or dawh, who wants to start a new game?

I'm also thinking of a new algorithm, but I'm far from over.

Thanks
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#66 Cherry Lane

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Posted 31 October 2010 - 12:55 PM

So, CherryLane or dawh, who wants to start a new game?

I'm also thinking of a new algorithm, but I'm far from over.

Thanks


I've been away for the weekend and haven't had a chance to work on mine. So don't wait for me, if anyone has another ready to try out.
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#67 dawh

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Posted 01 November 2010 - 03:12 PM

I've been away for the weekend and haven't had a chance to work on mine. So don't wait for me, if anyone has another ready to try out.

I was likewise busy all weekend, but I've gotten the algorithm good enough to suit our needs (or so I've arbitrarily determined), so I'll start the new topic as soon as I can. :thumbsup:
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#68 araver

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Posted 05 November 2010 - 02:42 PM

Marking it as solved.
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Summer of 2014:
Show the Mafia world you're back in action ... signup for Justice League Unleashed (Again) - Second Arc: Of Magic and Men. Come join the madness!  :thumbsup:
 
Puzzles open: Strange Creatures I Past puzzles: Mystery Operation Series: I, II, III, IV; Contamination Scenario;
Past games: Crack the Code Series: III, VII, IXPast mafia games: UN Mafia, UN Mafia II, Star Trek Mafia, TMM IV

Almost random quotes:
>> Not only is the universe stranger than we imagine, it is stranger than we can imagine.




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