import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        int current = 1;
        for (char c : s.toCharArray()) {
            if (c == 'L') {
                current *= 2;
            } else {
                current = current * 2 + 1;
            }
        }
        System.out.println(current);
    }
}