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{-
(* http://www.codecodex.com/wiki/Insertion_sort#Standard_ML *)
-}
import System.Random
qsort [] = []
qsort [x] = [x]
qsort (x:xs) = (qsort left) ++ [x] ++ (qsort right)
where (left, right) = part x xs
part pivot [] = ([], [])
part pivot (x:xs)
| x<pivot = (x:below, above)
| otherwise = (below, x:above)
where
(below, above) = part pivot xs
{-
main = print $ qsort [3,2,8,5]
-}
randomList :: Int -> IO([Int])
randomList 0 = return []
randomList n = do
r <- randomRIO (1,10000)
rs <- randomList (n-1)
return (r:rs)
main = do
list <- randomList 800000
let sorted = qsort list
print (take 10 sorted)
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