zdk.scala

import scala.annotation.tailrec
import scala.util.Random

object ZDK {
	val Z = "Z"
	val D = "D"
	val K = "K"
	@tailrec
	def zundoko(zd: List[String] = Nil): List[String] = zd match {
	   case D :: Z :: Z :: Z :: Z :: _ => zd.reverse
	   case _ => zundoko((if(Random.nextBoolean) Z else D) :: zd)
	}
	println(zundoko().mkString("") +K)
}