// Part 3 about finding a single tour using the Warnsdorf Rule//=============================================================// copy any function you need from files knight1.scala and// knight2.scalaobject CW7c {type Pos = (Int, Int) // a position on a chessboard type Path = List[Pos] // a path...a list of positions//(3a) Complete the function that calculates a list of onward// moves like in (1b) but orders them according to Warnsdorf’s // rule. That means moves with the fewest legal onward moves // should come first.//def ordered_moves(dim: Int, path: Path, x: Pos) : List[Pos] = ..//(3b) Complete the function that searches for a single *closed* // tour using the ordered moves function.//def first_closed_tour_heuristic(dim: Int, path: Path) : Option[Path] = ...//(3c) Same as (3b) but searches for *non-closed* tours. However, // you have to be careful to write a tail-recursive version as this // function will be called with dimensions of up to 40 * 40.//def first_tour_heuristic(dim: Int, path: Path) : Option[Path] = ...}