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araver
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One player plays the Evil Mastermind (that's me) who nukes the states of the USA 3 at a time, the other players play Hackers who seek to stop the Evil Mastermind. The Evil Mastermind plays by posting commands which activate missile strikes. Each command has a unique password, which is derived from the command by a hashing algorithm. The Evil Mastermind devises a different algorithm at the start of each game, and posts the passwords along with the commands. The Hackers will see the commands and passwords and from this they should try to deduce the hashing algorithm. The Hacker who does this first, and correctly figures out the password to the command "ABORT", stops the Evil Mastermind and wins the game. Anyone can join in at any time as a Hacker.

Now hashing algorithms can be exceedingly difficult to crack, but there are restrictions placed on the kind of algorithm that the Evil Mastermind can use:

1) The Evil Mastermind must be able to derive an alphanumeric password of fixed length from any word (password length 8 characters or less, you choose). It doesn't have to be a cipher in the sense that it can be decrypted to the original word, indeed the fixed length makes that impossible.

2) You must be able to do it in your head, with no external aids, in 40 seconds or less. You may look at the word you are hashing but you should not have to look at the previous letters of the password, since real-life passwords are generally shown as ***** as you type (although you may use previous letters as far as your memory can handle it). It's up to you to ensure that you can do all this. A really classy algorithm is one which fulfils this condition better (quick and easy to perform, in other words).

3) Although it is quite possible to hold an alphabetic substitution table in your head, and apply it quickly, I'll rule this out because in conjunction with other techniques it's too difficult to crack. Any technique that requires a large amount of information to be memorised in advance is not allowed. Caesar ciphers with a large shift pretty much fall into that category.

4) Consistency. This is a matter of good sportsmanship. For example, since "ABORT" is the target word, you can't have a rule that comes into play only when the sequence "BOR" occurs. All rules should be general enough that they come into play in at least half of the clues. The algorithm should not be geared toward the specific commands used in this game, but should work on any word.

Commands

There are 51 commands, these being the names of US states (used by the Evil Mastermind to nuke another state), plus the word "ABORT" (used by hackers to stop the Evil Mastermind).

Commands and passwords are all uppercase.

ABORT

ALABAMA

ALASKA

ARIZONA

ARKANSAS

CALIFORNIA

COLORADO

CONNECTICUT

DELAWARE

FLORIDA

GEORGIA

HAWAII

IDAHO

ILLINOIS

INDIANA

IOWA

KANSAS

KENTUCKY

LOUISIANA

MAINE

MARYLAND

MASSACHUSETTS

MICHIGAN

MINNESOTA

MISSISSIPPI

MISSOURI

MONTANA

NEBRASKA

NEVADA

NEWHAMPSHIRE

NEWJERSEY

NEWMEXICO

NEWYORK

NORTHCAROLINA

NORTHDAKOTA

OHIO

OKLAHOMA

OREGON

PENNSYLVANIA

RHODEISLAND

SOUTHCAROLINA

SOUTHDAKOTA

TENNESSEE

TEXAS

UTAH

VERMONT

VIRGINIA

WASHINGTON

WESTVIRGINIA

WISCONSIN

WYOMING

Game Play

The Evil Mastermind posts 3 commands at a time, with their passwords. The interval for doing this is undefined, no point in imposing restrictions. The Evil Mastermind chooses the commands, but should generally do requests as soon as possible.

Each Hacker may make one guess at the password for "ABORT" each time the Evil Mastermind posts commands. If someone makes multiple guesses in between clues, only the first one counts, but if they make a mistake and correct it, the Evil Mastermind can accept the correction.

There is no need for spoilers when guessing the password, although please use spoilers if you reveal the algorithm.

The first one to get the password for "ABORT" wins.

P.S. Alternatively if you've cracked the algorithm you can just use it to blow up more states if you're that way inclined (**per original Evil Mastermind's rules!)

- Host: octopuppy - Winner: fabpig

- Host: octopuppy - Winner: araver

- Host: araver - Winner: octopuppy

- Host: dawh - Winner: octopuppy

- Host: octopuppy - Winner: Vineetrika / araver,

- Host: Vineetrika - Winner: octopuppy

Edited by araver
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3 more states:

CONNECTICUT

QNOFCTIE

GEORGIA

GOTHJBGG

MASSACHUSETTS

ASSADHUT

I don't think anyone will understand it. It's so complicated. :unsure: :unsure:

It is just the beginning. After a while, given enough states, people usually begin to see patterns. Check out the list of the other games and try for yourself ;)

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Maine coming up ...

MAINE

NFOAJNFO

LOUSIANA

WKTJBPCM

MARYLAND

ASZMBPFM

24 down, 27 to go

Just FYI for anyone who might be confused, Louisiana works better when it's spelled correctly. :P

With any of these that use a shifting algorithm as part of the encryption, it's pretty easy to break the shift given the plaintext and ciphertext, but to figure out the algorithm itself can be a doozy... :wacko:

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Just FYI for anyone who might be confused, Louisiana works better when it's spelled correctly. :P

With any of these that use a shifting algorithm as part of the encryption, it's pretty easy to break the shift given the plaintext and ciphertext, but to figure out the algorithm itself can be a doozy... :wacko:

:duh: Confirming

LOUISIANA

WKTJBPCM

Guess I needed to eat something since it was early morning for me :D

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UTAH

TCJUTCJU

I cannot stop pondering some things, so if you're curios check the spoiler.

I was pretty sure I'd get a lot of attempts / brute force tries this time. Maybe there are fewer Hackers since it's Thanksgiving week, idk. Only dawh and octopuppy have expressed interest in it.

Anyway, my independent Hacker thoughts on this (which I had before posting the challenge):

IDEA 1) If I can't figure out an exact pattern but it seems that the algorithm chooses a starting letter first then I can start brute-forcing for a specific command by trying my-current-algorithm-best-shot on the command shifted by one position, two positions, etc. The number of possibilities is small.

IDEA 2) If I cannot accurately predict a letter in password that corresponds to a letter in command (i.e. there is no global function/ transformation that can be seen), then one of the following may be true:

EITHER there is a global rule/idea that changes the function depending on all the command itself (e.g. no of vowels in command / no of distinct vowels etc.) - e.g. Game 3, Game 6.

OR there is a more local rule that changes the outcome/transformation of a letter depending on the context in which this letter (e.g. left/right neighbors) - e.g. Game 5.

I used IDEA 1 in Game 5 and it would have taken me 5 tries without Vineetrika's correct hint for the starting position.

Also used IDEA 2 successfully in Game 5 - I used partial reasoning to predict the transformations for a particular command (ABORT) without actually having the whole rule or grasping its underlying logic.

I would have expected (from IDEA1) that someone might take a shot/more shots with an IDEA2-algorithm. Even without understanding its logic fully.

Just sayin' :)

Edited by araver
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