import scala.math._

object Main {
  def main(args: Array[String]) {
    val sc = new java.util.Scanner(System.in)
    val s = sc.nextLine

    var x = 1
    for (c <- s) c match {
      case 'L' => x = x * 2
      case 'R' => x = x * 2 + 1
    }
    println(x)
  }
}