Scalaで迷路生成（棒倒し）

Stick.scala

import scala.util.Random

object Stick {
	def printMaze(m:Map[(Int,Int), String])(implicit size:(Int,Int)) = {
		val w = size._1
		val h = size._2
		for(j <- 0 until h)
		{
			for(i <- 0 until w){
				m.get((i,j)) match {
					case Some(s) => print(s)
					case None => print(" ")
				}
			}
			println("")
		}
	}

	def aroundWallMap(implicit size:(Int,Int), wall:String) = {
		val w = size._1
		val h = size._2
		(for(i <- 0 until w) yield ((i,0) -> wall)) ++ (for(i <- 0 until w) yield ((i,h - 1) -> wall)) ++ (for(i <- 0 until h) yield ((0,i) -> wall)) ++ (for(i <- 0 until h) yield ((w - 1, i) -> wall)).toMap
	}
	def constantWallMap(implicit size:(Int,Int), wall:String) = {
		val w = size._1
		val h = size._2
		(for(i <- 0 to ((w - 3) / 2) ; j <- 0 to ((h - 3) / 2)) yield ((i * 2 + 2,j * 2 + 2) -> wall)).toMap
	}
	def wallStick(m:Map[(Int,Int), String])(implicit wall:String) = {
		var dst:Map[(Int,Int),String] = Map()
		m foreach(p => {
			var t = (new Random).shuffle(List((p._1._1, p._1._2 - 1), (p._1._1, p._1._2 + 1), (p._1._1 - 1, p._1._2), (p._1._1 + 1, p._1._2)))
			while(m.contains(t.head)){
				t = t.tail
			}
			dst += t.head -> wall
		})
		dst
	}
	def main(args:Array[String]) = {
		implicit val w = 40 + 3//2n
		implicit val h = 20 + 3
		implicit val size = (w,h)
		implicit val wall = "#"

		val a = constantWallMap
		val maze = a ++ wallStick(a) ++ aroundWallMap ++ Map((1,1) -> "S",(w - 2,h - 2) -> "G")
		printMaze(maze)
	}
}

z_stick.log

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