1 import CW8a._

     2 //type Pos = (Int, Int)    // a position on a chessboard 

     3 //type Path = List[Pos]    // a path...a list of positions

     4 

     5 def count_all_tours_urban(dim: Int) = {

     6   for (i <- (0 until dim).toList; 

     7        j <- (0 until dim).toList) yield count_tours(dim, List((i, j)))

     8 }

     9 

    10 

    11 assert(count_all_tours_urban(1) == List(1))

    12 assert(count_all_tours_urban(2) == List(0, 0, 0, 0))

    13 assert(count_all_tours_urban(3) == List(0, 0, 0, 0, 0, 0, 0, 0, 0))

    14 assert(count_all_tours_urban(4) == List(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0))

    15 assert(count_all_tours_urban(5) == List(304, 0, 56, 0, 304, 0, 56, 0, 56, 0, 56, 0, 64, 0, 56, 0, 56, 0, 56, 0, 304, 0, 56, 0, 304))

    16