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

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