CrossTheMaze.scala

object CrossTheMaze extends App {

  trait Direction {
    def dx: Int
    def dy: Int
  }
  case object North extends Direction {
    val (dx, dy) = (0, -1)
  }
  case object East extends Direction {
    val (dx, dy) = (1, 0)
  }
  case object South extends Direction {
    val (dx, dy) = (0, 1)
  }
  case object West extends Direction {
    val (dx, dy) = (-1, 0)
  }
  
  val Directions = Vector(North, East, South, West)

  class Maze(mazeString: String) {

    private val wall = {
      val middles = for (line <- mazeString.lines.toVector) yield true +: (for (c <- line) yield c == '#') :+ true
      val b = Vector.fill(middles.head.size)(true)
      b +: middles :+ b
    }

    def step(x: Int, y: Int, face: Direction): (Int, Int, Direction) = {
      
      val (left, right, back) = (North, South, West) //East
      if (!isWall(x+left.dx, y+left.dy)) (x+left.dx, y+left.dy, left)
      else if (!isWall(x+face.dx, y+face.dy))(x+face.dx, y+face.dy, face)
      else if (!isWall(x+right.dx, y+right.dy))(x+right.dx, y+right.dy, right)
      else (x+back.dx, y+back.dy, back)
    }

    def isWall(coord: (Int, Int)): Boolean = coord match { case (x, y) => wall(x)(y) }

  }

  def findPath(maze: Maze, sx: Int, sy: Int, ex: Int, ey: Int): Option[String] = None

  def process(lineIn: Iterator[String])(lineOut: String => Unit) =
    for (i <- 1 to lineIn.next().toInt) {
      val n = lineIn.next()
      val ss = lineIn.next().split(' ').map(_.toInt)

      //      lineOut(s"Case #$i: ${sort(ss: _*) mkString " "}")
    }

  val writer = new java.io.PrintWriter("c.large.out")
  try {
    process(io.Source.fromFile("C-large-practice.in").getLines)(writer.println)
  } finally {
    writer.flush(); writer.close()
  }

}