whops... i did check it, but that was a copypaste mistake. buggy: > tm_parallelizable_v1 = \n -> sum . takeWhile (>0) $ map (div n) fives > where fives = iterate (*5) 1
should be: > tm_parallelizable_v1 = \n -> sum . takeWhile (>0) $ map (div n) fives > where fives = iterate (*5) 5 - marc Am Freitag, 24. August 2007 schrieben Sie: > Hi Marc > > First off, thanks for your reply. > >> tm_parallelizable_v1 = \n -> sum . takeWhile (>0) $ map (div n) fives > >> where fives = iterate (*5) 1 > Did you check this one? IMHO I think it's producing the 'wrong' answer. > > *Main> tm_parallelizable_v1 100 > 124 > (0.00 secs, 0 bytes) > > *Main> tm 100 > 24 > (0.00 secs, 0 bytes) > > If comparing the result to the other variants is accepted as a sort > of proof. ;-) > > But calculating the number of trailing zero's of n! is a matter of > counting powers of five in the factorized n!: f.e.: > > 10! = 1 2 3 2^2 5 2*3 7 2^3 3^2 2*5 > --> 5^2 --> picking up enough powers of 2 --> (2*5)^2 = 100 > > So you will have to correct your 'fives' to f.e. > > fives = tail $ iterate (*5) 1 > > > > Regards > > > @@i > > >
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