#include "iostream"
using namespace std;

char letter[50];
int ans = 1;

int main() {
	cin >> letter;
	for (int i = 0; letter[i] == 'L' || letter[i] == 'R'; i++) {
		if (letter[i] == 'L')ans *= 2;
		if(letter[i]=='R') ans = ans * 2 + 1;
	}
	cout << ans << "\n";
}