Change package structure

src/main/scala/ninetyNineScalaProblems/lists/Problem14.scala

@@ -0,0 +1,18 @@
+package ninetyNineScalaProblems.lists
+
+import scala.annotation.tailrec
+
+object Problem14:
+    def duplicateElements(list: List[Any]): List[Any] =
+        @tailrec
+        def loop(cursor: List[Any], acc: List[Any]): List[Any] =
+            cursor match
+                case e :: tail =>
+                    loop(tail, e :: e :: acc)
+                case Nil =>
+                    acc
+
+        loop(list, List()).reverse
+
+    def duplicateElements2(list: List[Any]): List[Any] =
+        list.flatMap(i => i :: List(i))