GameOfLife.scala

object GOL extends App {
  type Cell = (Int,Int)
	type Step = List[Cell]

	lazy val motifvoisinage:Step = {
		val iii = (-1 to 1)
		iii.flatMap(x => iii.map( _ -> x)).filter(_ != (0,0)).toList
	}

	def add(c1:Cell, c2:Cell):Cell = (c1._1 + c2._1, c2._2 + c1._2)

	def voisinage(s:Step) = for(i <- s; j <- motifvoisinage) yield (add(i,j))

	def nextStep(s:Step):Step = {
		voisinage(s).groupBy(x=> x).mapValues(_.size).filter(t => {
			val (k,v) = t
			(v == 3) ||
			(v == 2 && s.contains(k))}).keys.toList
	}


	def printStep(s:Step) {
	def rangeFromList(li:List[Int]) = {li.min to li.max}
  
	for ( x <- rangeFromList(s.map(_._1))) {
	  println((for (y <- rangeFromList(s.map(_._2))) yield {
	    if(s.contains((x,y))) "X" else " "}).mkString)
    }
  }


     var mystep = glider
     (1 to 100).foreach ( i => {
     	printStep(mystep)
     	println("-----------")
     	mystep = nextStep(mystep)


     })



  lazy val glider = blinker ::: List((1,3), (2,2)) ::: List((-1,-1),(-2,-2), (-1,-2),(-2,-1))

  lazy val blinker = List((0,1),(0,2),(0,3))
}