import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.InputMismatchException;

public class NationalHighway {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        try{
            String string = scanner.next();
            if(string.length() != 0){
                //Pattern pattern = Pattern.compile("*[R|L|^$]*");
                Pattern pattern = Pattern.compile(".*[R|L].*");
                Matcher matcher = pattern.matcher(string);
                if(!matcher.find()){
                    System.out.println("文字列はRかLだけで入力してください");
                    System.exit(0);
                }
                if(string.length()<0 || string.length() > 30){
                    System.out.println("文字列は1以上30以下で入力してください");
                }
            }
            
            int Road = 1;
            char[] NewString = string.toCharArray();
             
            for(int i = 0 ; i < string.length() ; i++){
                System.out.print("test");
                if(NewString[i] == 'R'){
                    Road = Road * 2 + 1;
                }else if(NewString[i] == 'L'){
                    Road = Road * 2 ;
                }else{
                    //何もしない
                }
            }
            System.out.println(Road);
            
        }catch(InputMismatchException e){
            System.out.println("");
        }catch(Exception E){
            System.out.println("予期せぬエラーです");
        }
    }
}