de-duplicate

gistfile1.scala

def deduplicate[T](l: List[T]): List[T] = {
  def deduplicate_acc[T](l: List[T], acc: List[T]): List[T] = l match {
    case x :: xs if acc contains x => deduplicate_acc(xs, acc)
    case x :: xs => deduplicate_acc(xs, acc :+ x)
    case Nil => acc
  }
  deduplicate_acc(l, List.empty[T])
}

println(deduplicate(List(1,2,2,3,4,5,1,4,6,8,3))) // List(1, 2, 3, 4, 5, 6, 8)