I recommend that you just figure out how many items is way more than you will ever have -- let's say, maybe 2^80 -- and then square it because of the birthday paradox. So if your random number has at least 160 bits then you can stop worrying about collisions and spend more time worrying about all the bigger problems your system has. :-)
Regards, Zooko _______________________________________________ p2p-hackers mailing list p2p-hackers@lists.zooko.com http://lists.zooko.com/mailman/listinfo/p2p-hackers
