2016 Update

Task/Power-set/Scala/power-set-3.scala

@@ -0,0 +1,7 @@
+def powerset[A](s: Set[A]) = {
+  def powerset_rec(acc: List[Set[A]], remaining: List[A]): List[Set[A]] = remaining match {
+    case Nil => acc
+    case head :: tail => powerset_rec(acc ++ acc.map(_ + head), tail)
+  }
+  powerset_rec(List(Set.empty[A]), s.toList)
+}