Problem 16

src/main/scala/ninetyNineScalaProblems/Problem16.scala

@@ -0,0 +1,17 @@
+package ninetyNineScalaProblems
+
+import scala.annotation.tailrec
+
+object Problem16:
+    def dropEveryNthElement(n: Int, list: List[Any]): List[Any] =
+        @tailrec
+        def loop(cursor: List[Any], acc: List[Any], count: Int): List[Any] =
+            cursor match
+                case e :: tail if count == n =>
+                    loop(tail, acc, 1)
+                case e :: tail =>
+                    loop(tail, e :: acc, count + 1)
+                case Nil =>
+                    acc
+
+        loop(list, List(), 1).reverse

src/test/scala/ninetyNineScalaProblems/Problem16Suite.scala

@@ -0,0 +1,17 @@
+package ninetyNineScalaProblems
+
+import scala.compiletime.ops.boolean
+
+class Problem16Suite extends munit.FunSuite:
+    List(
+        ((0, List(1, 2, 3, 4)), List(1, 2, 3, 4)),
+        ((0, List()), List()),
+        ((1, List(1, 2, 3, 4)), List()),
+        ((1, List(1)), List()),
+        ((2, List(1, 2, 3, 4, 5, 6, 7)), List(1, 3, 5, 7)),
+        ((3, List(1, 2)), List(1, 2)),
+        ((3, List()), List()),
+    ).foreach:
+        case ((n, list), expected) =>
+            test(s"dropEveryNthElement returns [$expected]"):
+                assertEquals(Problem16.dropEveryNthElement(n, list), expected)