import java.util.*;
import java.io.*;

public class Exercise124{
  public static void main (String[] args) throws IOException{

    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    String s = new String(in.readLine());
    char[] sa = s.toCharArray();
    int a = 1;
    for(int lOrR: sa){
      if(lOrR == 'L'){
        a *= 2;
      }else{
        a = a * 2 + 1;
      }
    }
    System.out.println(a);
	}
}