--- a/marking3/knight1_test5.scala	Sun Dec 09 01:36:49 2018 +0000
+++ b/marking3/knight1_test5.scala	Mon Dec 10 02:23:30 2018 +0000
@@ -1,6 +1,6 @@
 
-type Pos = (Int, Int)    // a position on a chessboard 
-type Path = List[Pos]    // a path...a list of positions
+//type Pos = (Int, Int)    // a position on a chessboard 
+//type Path = List[Pos]    // a path...a list of positions
 
 def add_pair_urban(x: Pos)(y: Pos): Pos = 
   (x._1 + y._1, x._2 + y._2)