#include <iostream>
#include <algorithm>
#include <vector>
#include<string>

using namespace std;
int main(){
	string s;
	int n = 1;
	cin >> s;
	for (int i = 0; i < s.size(); i++) {
		if (s[i] == 'L') {
			n *= 2;
		} else {
			n *= 2;
			n += 1;
		}
	}
	cout << n << "\n";
	return 0;
}