task 1

src/Hanoi.scala

@@ -0,0 +1,32 @@
+import scala.collection.mutable
+
+class Hanoi(val n: Int, val left: Char, val mid: Char, val right: Char) {
+  val lists: mutable.HashMap[Char, mutable.Stack[Int]] = new mutable.HashMap()
+  lists(left) = mutable.Stack.range(1, n + 1)
+  lists(mid) = mutable.Stack.empty
+  lists(right) = mutable.Stack.empty
+
+  def move(from: Char, to: Char): Unit = {
+    val i: Int = lists(from).pop()
+    println(s"Moving disk $i from $from->$to")
+    lists(to).push(i)
+  }
+
+  def solve(): Unit = {
+    hanoi(n, left, mid, right)
+  }
+
+  private def hanoi(n: Int, start: Char, aux: Char, end: Char): Unit = {
+    if (n == 0) return
+    hanoi(n - 1, start, end, aux)
+    move(start, end)
+    hanoi(n - 1, aux, start, end)
+  }
+}
+
+object Hanoi {
+  def main(args: Array[String]): Unit = {
+    val hanoi: Hanoi = new Hanoi(3, 'A', 'B', 'C')
+    hanoi.solve()
+  }
+}