Initial data commit

Task/Damm-algorithm/Scala/damm-algorithm.scala

@@ -0,0 +1,29 @@
+import scala.annotation.tailrec
+
+object DammAlgorithm extends App {
+
+  private val numbers = Seq(5724, 5727, 112946, 112949)
+
+  @tailrec
+  private def damm(s: String, interim: Int): String = {
+    def table =
+      Vector(
+        Vector(0, 3, 1, 7, 5, 9, 8, 6, 4, 2),
+        Vector(7, 0, 9, 2, 1, 5, 4, 8, 6, 3),
+        Vector(4, 2, 0, 6, 8, 7, 1, 3, 5, 9),
+        Vector(1, 7, 5, 0, 9, 8, 3, 4, 2, 6),
+        Vector(6, 1, 2, 3, 0, 4, 5, 9, 7, 8),
+        Vector(3, 6, 7, 4, 2, 0, 9, 5, 8, 1),
+        Vector(5, 8, 6, 9, 7, 2, 0, 1, 3, 4),
+        Vector(8, 9, 4, 5, 3, 6, 2, 0, 1, 7),
+        Vector(9, 4, 3, 8, 6, 1, 7, 2, 0, 5),
+        Vector(2, 5, 8, 1, 4, 3, 6, 7, 9, 0)
+      )
+
+    if (s.isEmpty) if (interim == 0) "✔" else "✘"
+    else damm(s.tail, table(interim)(s.head - '0'))
+  }
+
+  for (number <- numbers) println(f"$number%6d is ${damm(number.toString, 0)}.")
+
+}