#include<iostream>
#include<string>
using namespace std;
int main() {
	string S;
	int kokudo = 1;
	cin >> S;
	for (int i = 0; i < S.length(); i++) {
		if (S.at(i) == 'L') kokudo *= 2;
		if (S.at(i) == 'R') kokudo = kokudo * 2 + 1;
	}
	cout << kokudo << endl;
	return 0;
}