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

int main() {
	string s;
	cin >> s;
	int ans = 1;
	for (auto i = s.begin(); i != s.end(); i++)
	{
		if (*i == 'L')
		{
			ans = 2 * ans;
		}
		else
		{
			ans = 2 * ans + 1;
		}
	}
	cout << ans << endl;

	return 0;
}