[Haskell-beginners] Re: [Haskell-cafe] Re: permuting a list

Heinrich Apfelmus apfelmus at quantentunnel.de
Mon Feb 16 03:41:50 EST 2009

Alberto Ruiz wrote:
> How about using random doubles?
> randomPerm xs = fmap (map snd . sort . flip zip xs) rs
>     where rs = fmap (randoms . mkStdGen) randomIO :: IO [Double]

Interesting idea. The chance of duplicates should be negligible now, but
that's because we're using a large amount of random bits, far more than
n! would require.



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