Problem 03

src/main/scala/ninetyNineScalaProblems/Problem03.scala

@@ -0,0 +1,21 @@
+package ninetyNineScalaProblems
+
+import scala.annotation.tailrec
+
+object Problem03:
+    def nthElement(list: List[Any], n: Int): Option[Any] =
+        @tailrec
+        def loop(cursor: List[Any], acc: Int): Option[Any] =
+            cursor match
+                case e :: tail if acc == n =>
+                    Some(e)
+                case e :: tail =>
+                    loop(tail, acc + 1)
+                case Nil =>
+                    None
+
+        loop(list, 0)
+
+object Problem03Stdlib:
+    def nthElement(list: List[Any], n: Int): Option[Any] =
+        list.drop(n).headOption

src/test/scala/ninetyNineScalaProblems/Problem03Suite.scala

@@ -0,0 +1,13 @@
+package ninetyNineScalaProblems
+
+class Problem03Suite extends munit.FunSuite:
+    List(
+        ((List(1, 2, 3, 4, 5), 0), Some(1)),
+        ((List(1, 2, 3, 4, 5), 2), Some(3)),
+        ((List(1), 1), None),
+        ((List(), 0), None)
+    ).foreach:
+        case ((list, n), expected) => 
+            test(s"nthElement returns [$expected]"):
+                assertEquals(Problem03.nthElement(list, n), expected)
+                assertEquals(Problem03Stdlib.nthElement(list, n), expected)