--- a/marking3/knight_test9.scala	Tue Feb 04 11:20:31 2020 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,28 +0,0 @@
-
-//type Pos = (Int, Int)
-//type Path = List[Pos]
-
-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
-}
-
-
-val ts70 = tour_on_mega_board(70, List((0,0))).get
-assert(correct_urban(70)(ts70) == true)
-