Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?
DEAL: For $25 - Add A Second Phone Number To Your Smartphone for life! Use promo code SLASHDOT25. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. Check out the new SourceForge HTML5 internet speed test! ×

Submission + - New Elliptic Curve Cryptography Record

deian writes: Cryptography researchers Joppe W. Bos and Marcelo E. Kaihara, Thorsten Kleinjung, Arjen K. Lenstra and Peter L. Montgomery have just announced that they have set a new record for the elliptic curve discrete logarithm problem (ECDLP) by solving it over a 112-bit finite field. The previous record was for a 109-bit prime field and dates back from October 2002. Their calculation was done on the EPFL cluster of more than 200 PS3s (same one used to create the Rogue CA certificates and demonstrate a reproducible attack on MD5 algorithms). On the PS3, the effort is equivalent to about 14 full 56-bit DES key searches!

Submission + - What is the best algorithm for HAND sorting? 2

EricHsu writes: "I'm a teacher and I've often had to sort stacks of 20-100 papers by last name. For I while I did what I suppose most hand sorters do: I made a new stack and added new papers in order. I believe this is basically insertion sort, right?

After a while, this felt inefficient, particular since it's relatively slow to flip through the papers. So I tried a kind of bucket sort where I first sorted papers into four piles of lead letter ranges, like [A-F][G-M][N-S][T-Z], and then did an insertion sort on the piles. This seemed to go faster, but it was a bit confusing to remember which letters bounded each pile.

It seemed to me that someone must have thought about this harder that I have and that such a geek could be found on Slashdot. In particular, it seems to me that one could do a somewhat detailed study of hand-sorting algorithms by modifying analyses of computer sorting algorithms, which usually take into account number of comparisons and memory usage etc, taking into account human parameters like difficulty of flipping papers, difficulty of remembering the algorithm, how many papers one can hold easily in a single hand, difficulty of accessing piles as the number grows.

So, any careful analyses out there? Or failing that, any great hand sorting algorithms?"

Slashdot Top Deals

Nonsense. Space is blue and birds fly through it. -- Heisenberg