Grand Master Turing once dreamed that he was a machine. When he awoke he exclaimed: "I don't know whether I am Turing dreaming that I am a machine, or a machine dreaming that I am Turing!."-- The Tao Of Programming
The other day I dreamt an idea for a small game. I've been coding it in my free time since monday. This is pretty exciting.
jarod: Advogato is an international forum. Please try to use English. It's a matter of common courtesy.
You might also like to check out the paper A Killer Adversary for Quicksort, in case you haven't already. :)
So, Team Bandersnatch (bi and I) got in the top-50, which entitles us to t-shirts. I did one problem, he did three. :)
I'd post my solution to problem 6, like he did, but it looks fugly - it took a lot of hammering to make the square peg fit in the star-shaped hole.
Some of the problems were hardcore. None of the teams did problems 3 or 4.
Buzzword Assault
A company called D-Wave demo'ed an alleged superconducting 16-qubit quantum computer. Their PR department seems to claim it's able to solve NP-complete problems in polynomial time, which sounds like BS, but the thing looks pretty darn cool anyway. In both senses of the word (ha, ha).
q = ((a<<3) + a) >> 6
q = ((a<<6) + (a<<3) + a) >> 9
q = ((a<<9) + (a<<6) + (a<<3) + a) >> 12
q = ((a<<12) + (a<<9) + (a<<6) + (a<<3) + a) >> 15
...
and so on (in binary, 1/7 is .001001001...). Optionally, the result can be fixed with something like
r = a - q*7; while (r >= 7) { q++; r -= 7; }
The multiplication by 7 can be replaced with shifts and adds, of course.
My performance was dismal. I did the easy problem, then moved straight to the hard one. Then I threw away 20 minutes because I jumped straight to the code before understanding completely the problem statement and then had to start all over again, wasted another 20 minutes tracking down a stupid off-by-one bug, panicked for about 5 minutes, and finally ended up submitting a /wrong/ solution. Guess I need to work on the think-crush-under-pressure thing.
What makes it so frustrating is that the problem was not really that hard, and I was able to concoct a correct solution (here) without major difficulties afterwards, when the time pressure was gone.
Gah.
The qualification round was easier than I expected. It's probably just meant to filter out the curious. I was able to do both problems in about 30 minutes, and qualified to the next phase.
Tupper's Self-Referential Formula
... seems to be making the rounds on the internet. Two different people sent me the link. It's cute, but there's nothing magical about it, really - perhaps if some people look at it as a simple Perl script they'll realize that it's just a way to rasterize the big number, and the bitmap could be anything.
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