"Simon Brenner" <[EMAIL PROTECTED]> writes: > The key is letting haskell be lazy and produce the output one item at > a time.
True. > This solution goes up to 100k in 25M of heap and up to 400k in 200M of > heap. While working better, the space requirement seems to be (at > least almost) quadratic, so this is probably not a complete solution > to your problem (unless all you really needed was those 10k elements, > or at most 400k). Hmmm... what were you testing? :m Data.Array Prelude Data.Array> let test upb = let a = listArray (1,upb) (repeat False) in a//map (\n->(2^n,not (a!(2^n)))) [1..floor (logBase 2 $ fromIntegral upb)] ! upb (0.02 secs, 1567316 bytes) Prelude Data.Array> test 100000 False (0.02 secs, 1310876 bytes) Prelude Data.Array> test 400000 False (0.09 secs, 3710792 bytes) Prelude Data.Array> test 800000 False (0.16 secs, 6913864 bytes) Prelude Data.Array> -- Jón Fairbairn [EMAIL PROTECTED] _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
