Initial data commit

Task/Power-set/Scala/power-set-1.scala

@@ -0,0 +1,9 @@
+import scala.compat.Platform.currentTime
+
+object Powerset extends App {
+  def powerset[A](s: Set[A]) = s.foldLeft(Set(Set.empty[A])) { case (ss, el) => ss ++ ss.map(_ + el)}
+
+  assert(powerset(Set(1, 2, 3, 4)) == Set(Set.empty, Set(1), Set(2), Set(3), Set(4), Set(1, 2), Set(1, 3), Set(1, 4),
+    Set(2, 3), Set(2, 4), Set(3, 4), Set(1, 2, 3), Set(1, 3, 4), Set(1, 2, 4), Set(2, 3, 4), Set(1, 2, 3, 4)))
+  println(s"Successfully completed without errors. [total ${currentTime - executionStart} ms]")
+}

Task/Power-set/Scala/power-set-2.scala

@@ -0,0 +1 @@
+def powerset[A](s: Set[A]) = (0 to s.size).map(s.toSeq.combinations(_)).reduce(_ ++ _).map(_.toSet)

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)
+}