Задачка от Dzone: Remove Duplicates From a Linked List

Задача:

Given an unsorted linked list, and without using a temporary buffer, write a method that will delete any duplicates from the linked list.  

http://java.dzone.com/articles/thursday-code-puzzler-remove

Моё решение на Scala:

 

def removeDuplicates[A](li: List[A]): List[A] =
  li match{
   case Nil => li
   case h::Nil => li
   case h::t => if(t.contains(h)) removeDuplicates(t) else h::removeDuplicates(t)
  }