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

int main() {
	int ans;
	string S;
	cin >> S;

	int i = 0;
	ans = 1;
	while(S[i]) {
		if(S[i] == 'L') ans *= 2;
		if(S[i] == 'R') ans = ans*2+1;
		i++;
	}
	cout << ans << endl;

	return 0;
}