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