gol.scala

gistfile1.scala

case class Position(x: Int, y: Int)

object Grid {
  val Width = 10
  val Height = 10

  val grid = Map(
    Position(0, 0) -> true
  )


  def go(grid: Set[Position]): Set[Position] = {
    //(0 to Width)

    val positions = (for {
      x <- 0 until Width
      y <- 0 until Height
    } yield Position(x, y)).toList

    positions.foldLeft(Set.empty[Position]) {
      (newGrid, position) =>
        if (grid.contains(position)) {
          val px = position.x
          val py = position.y
          val neighbours = Set(Position(px + 1, py + 1),
                                Position(px, py + 1),
                                Position(px - 1, py +1),
                                Position(px - 1, py -1),
                                Position(px, py-1),
                                Position(px+1,py-1),
                                Position(px+1,py)
                                )
          val liveNeighbours = neighbours.intersect(grid)
          if (liveNeighbours.size < 2 || liveNeighbours.size > 3) newGrid
          else newGrid + position
        } else newGrid
    }
  }
}