Marcov chain

gistfile1.scala

trait State {
  import State._

  val seq: Seq[(Double, State)]

  def next: State =
    (seq sortWith { (s1, s2) =>
      (s1._1 * randValue) > (s2._1 * randValue)
    }).head._2

}

case object A extends State {
  override lazy val seq: Seq[(Double, State)] = Seq(0.7 -> A, 0.3 -> B)
}

case object B extends State {
  override lazy val seq: Seq[(Double, State)] = Seq(0.8 -> A, 0.2 -> B)
}

object State {
  val rand = new scala.util.Random
  def randValue = rand.nextDouble
}


def rec(st: State, c: Int = 0): Int = {
  if (c == 100) 0
  else {
    val next = st.next
    println(s"$c : $st -> $next")
    rec(next, c + 1)
  }
}

rec(A)