import java.math.*;
import java.util.*;

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