Yeah, the 10000 first primes takes about 0.1 seconds in Haskell too using the code I posted. On Feb 10, 2007, at 21:49 , Creighton Hogg wrote:

On 2/10/07, Peter Berry wrote: Gah! Gmail has really broken defaults for posting to lists.

On 10/02/07, Creighton Hogg wrote:

...

Hello Haskell-ers, So a friend and I were thinking about making code faster in Haskell, and I was wondering if there was a way to improve the following method of generating the list of all prime numbers. It takes about 13 seconds to run, meanwhile my friend's C version took 0.1. I'd love to learn a bit more about how to optimize Haskell code.

Which subproblem takes 13 seconds? (Surely generating a list of all primes will take an infinite amount of time, since there are infinitely many of them?)

Apparently I shouldn't send e-mails quickly, as it comes out as gibberish. It was the first 10000. The thirteen seconds was just approximate, but it showed the C one was much faster, which I figured was because I had constructed it poorly. Apparently I had, and I even managed to type it in wrong.

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