let rec qsort = function | []   -> []
                         | h::t -> qsort (List.filter ((>=) h) t)
                                   @ [h] @
                                   qsort (List.filter ((<) h) t)

let r = new System.Random()
[<EntryPoint>]
let main() = 
        let sample = List.init 300 (fun _-> r.Next(System.Int32.MaxValue))
        System.Console.WriteLine(qsort sample)