#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
    string s;
    getline(cin, s);

    int road = 1;
    for(int i=0; i<s.length();  i++){
        road *= 2;
        road += s[i] == 'L' ? 0 : 1;
    }

    cout << road << endl;

    return 0;
}