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Task/Quickselect-algorithm/Haskell/quickselect-algorithm.hs

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+import Data.List (partition)
+
+quickselect :: Ord a => Int -> [a] -> a
+quickselect k (x:xs) | k < l     = quickselect k ys
+                     | k > l     = quickselect (k-l-1) zs
+                     | otherwise = x
+  where (ys, zs) = partition (< x) xs
+        l = length ys
+
+main :: IO ()
+main = do
+  let v = [9, 8, 7, 6, 5, 0, 1, 2, 3, 4]
+  print $ map (\i -> quickselect i v) [0 .. length v-1]