import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String s = sc.next();
    long ans = 1;
    String crlf = System.getProperty("line.separator");
    if(!(s.equals(crlf))) {
      for(int i = 0; i < s.length(); i++) {
        if(s.charAt(i) == 'L') {
          ans *= 2;
        } else {
          ans = 2 * ans + 1;
        }
      }
    }
    System.out.println(ans);
  }
}