#include <iostream>
#include <string>
using namespace std;

int main(){   
	int a = 1;
	string s;
	cin >> s;
	for(int i = 0; i < s.length(); i++){
		if(s[i] == 'L'){
			a *= 2;
		}else{
			a = a * 2 + 1;
		}
	}
	cout << a << endl;
}