Am Freitag 19 März 2010 02:56:36 schrieb zaxis: > %cat Test.hs > module Test(mcombs) > where > import Data.List > > mcombs = foldr (flip (>>=) . f) [[]] where f x xs = [x:xs,xs] > > %ghc -c -O2 Test.hs > %ghci > > > :l Test > > Ok, modules loaded: Test. > > > :set +s > > length $ mcombs [1..20] > 1048576 > (0.06 secs, 56099528 bytes) > > > length $ mcombs [1..50] > > ^CInterrupted. >
Yes, 2^50 = 1125899906842624. If your computer generated 10^9 sublists per second, you'd wait more than ten days for the answer. Since something like 25 million - 100 million per second is more in the region of what ordinary computers can achieve, it'd rather be three months to over a year. Prelude Parts> mcombs [1 .. 50] !! 100000000 [1,2,3,4,5,6,7,8,10,11,12,13,18,20,26,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50] (4.35 secs, 5254369992 bytes) Prelude Parts> length $ replicate (10^8) () 100000000 (2.10 secs, 2806344336 bytes) Really, not bad, IMO. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
