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buckysrevenge

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Yeah, as Brandon said in the message, something so simple, yet so effective is really cool.

Personally I'm significantly more familiar with codes and ciphers than I am with compression techniques (though I have a basic knowledge of them), and knowing it was some kind of transposition, and seeing that the dimensions were very regular etc meant not questioning the assumption that such a method would be exclusive to cryptography.

Now, thanks to this puzzle I've learned quite a bit more about compression than I did (still not much though) which is always a good outcome from being wrong.

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Yeah, as Brandon said in the message, something so simple, yet so effective is really cool.

Personally I'm significantly more familiar with codes and ciphers than I am with compression techniques (though I have a basic knowledge of them), and knowing it was some kind of transposition, and seeing that the dimensions were very regular etc meant not questioning the assumption that such a method would be exclusive to cryptography.

This was our big slip-up and the reason why I'm kicking myself even harder for not recognising the compression applications. We got way too bound up in general crypto and forgot the precedent of using things like TLS and QR codes - data encoding techniques that underpin everyday technology.

Now, thanks to this puzzle I've learned quite a bit more about compression than I did (still not much though) which is always a good outcome from being wrong.

Yes! Again like TLS and QR I knew the broad-strokes steps involved in BZ2, but zilch about the nitty-gritty details. Now I've spent an evening researching and putting together the skeleton of a python BZ2 implementation, it'll be terrible and will never actually be used for anything as there's a billion things out there that do it better (probably several in python), but there's a simple joy in implementing these kinds of algorithms for yourself and seeing them work, and its something I just don't do since programming became my day job.

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Ah well, we did pretty well, all told.

The bit that really tripped me up was that it didn't feel plausible to me that there was an algorithm that can sort letters together and also be reversible, without requiring a key or somesuch. Like the solution says - it feels a bit like magic, so I think that was stopping me from making the leap that the whole point was to bunch the letters together. So I was right in that the letters weren't being deliberately placed together in some irreversable process and that it was a natural part of the algorithm. I just didn't then see 'because that's what the algorithm is GOOD for, because...'

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You all did great :D

This was my favorite puzzle to watch get worked out. I learned new things about BWT from the thoughtful observations you were making, and your collective cleverness gave me new ideas...

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bwt.PNG

Thanks to my friend Kieran for some help in sorting out some of the more technical biz of reversing that.

Looks great! But what happened to the $ sign?

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bwt.PNG

Thanks to my friend Kieran for some help in sorting out some of the more technical biz of reversing that.

Looks great! But what happened to the $ sign?

It was the end of file marker

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You all did great :D

This was my favorite puzzle to watch get worked out. I learned new things about BWT from the thoughtful observations you were making, and your collective cleverness gave me new ideas...

It was definitely my favourite to participate in. With the QR code it was a logical exercise, but once you knew it was a nonagram it was just a matter of filling it in. The website puzzle was something I loved the idea of, but didn't have the skill to participate along every step of the way, even if I knew the principles of what was going on.

This one was, to repeat ourselves, more like a magic trick where we were analyzing it every single way we could, looking at a potential brute force method of solving it, only to figure out the simple, subtle trick at the last minute. I LOVE that aspect of magic tricks. it's also why I'm such a fan of procedural generation - seeing something super complex and interesting, all designed from a simple algorithm. I think that's my favourite thing about programming in general actually.

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