diff -r a057dc4457fc -r 87b9e3e2c1a7 marking/knight3b_test.scala
--- a/marking/knight3b_test.scala	Tue Oct 29 11:11:44 2019 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,38 +0,0 @@
-
-import scala.concurrent._
-import scala.concurrent.duration._
-import ExecutionContext.Implicits.global
-import scala.language.postfixOps 
-
-
-def add_pair_urban(x: Pos)(y: Pos): Pos = 
-  (x._1 + y._1, x._2 + y._2)
-
-def is_legal_urban(dim: Int, path: Path)(x: Pos): Boolean = 
-  0 <= x._1 && 0 <= x._2 && x._1 < dim && x._2 < dim && !path.contains(x)
-
-def moves_urban(x: Pos): List[Pos] = 
-  List(( 1,  2),( 2,  1),( 2, -1),( 1, -2),
-       (-1, -2),(-2, -1),(-2,  1),(-1,  2)).map(add_pair_urban(x))
-
-def legal_moves_urban(dim: Int, path: Path, x: Pos): List[Pos] = 
-  moves_urban(x).filter(is_legal_urban(dim, path))
-
-def correct_urban(dim: Int)(p: Path): Boolean = p match {
-  case Nil => true
-  case x::Nil => true
-  case x::y::p => 
-    if (legal_moves_urban(dim, p, y).contains(x)) correct_urban(dim)(y::p) else false
-}
-
-def correct_closed_urban(dim: Int)(p: Path) =
-  correct_urban(6)(p) &&  moves_urban(p.head).contains(p.last)
-
-lazy val f = Future {
-
-  val tsc = first_closed_tour_heuristic(6, List((3, 3))).get
-  assert(correct_closed_urban(6)(tsc) == true)
-
-}
-
-Await.result(f, 300 second)