2 pieces of gaming history
today i bought 'pokemon blue' for the game boy and 'duke nukem 3d' for the pc (query the FIRST EVER genuinely 3d shoot 'em up?) for £1.99 each at a car boot sale.
in the second world
they have the internet, but no scroll wheels on their mice, and it's just not the same.
sorting and scrambling
thinking about sorting algorithms today and wondering whether in general a sorting algorithm can be reversed (with some randomness thrown in) to create a algorithm for effective shuffling. this might yield very efficient ways of scrambling things into random permutations, since sorting algorithms are highly efficient ways of transforming any one of all possible permutations into one unique one. you see, it's difficult to shuffle quickly and know that you have shuffled well enough not to have excluded any possible order of say a pack of cards.
thinking about quicksort
(of which more about my personal adaptation anon) its clear that one single step is roughly analogous to the reverse of one 'riffle shuffle' of a pack of cards. how to invert the whole, recursive procedure is another story...
if i was trying to protect an important system from unauthorized access by hackers (crackers), i would offer a large cash reward to anyone who breached it in a significant way, but DIDN'T do ANY fraud or vandalism, also promise not to prosecute. if you had broken into someone's system, and could get the kudos for having done so and a LOT of money, why would you bother to deface a website, or attempt theft unless you were certain you could get away with it?
you in turn encourage people to bring your security holes to your attention w/o causing real harm. it would have to be the real system though, and not a decoy/honeypot, otherwise people would breach the dummy setup for the money, and the real one to say they did.
when did police cars stop being white and start being silver? i noticed because there were about 4 of them parked at the end of my road yesterday and the day before.
i saw two muslim ladies in headscarves driving a car with one of those £9000 paintjobs that change colour depending on the angle you look at them from..
and saw schoolboys brandishing sticks on their way home in 2 different places today, and wondered, which was first used as a weapon, the stick or the stone?
why do they only make Diet
Coke in lemon and lime flavours? i hate Diet Coke.
can you find
number x btw 0 and 1 such that the decimal expansions of both x and x2
do not contain any 0's? More than one solution exists ;)
A fall is defined as:
"An event which results in a person coming to rest UN-intentionally on the ground or other lower level, not as a result of major intrinsic event such as a stroke or overwhelming hazard"Tinnetti et al. 1998
thought for the week
"politics is not mathematics" - the iraqi prime minister