#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main()
{
    string s;
    cin >> s;

    ll ans = 1;

    for (int i = 0; i < s.size(); ++i)
    {
        if (s[i] == 'L')
        {
            ans *= 2;
        }
        else
        {
            ans = ans * 2 + 1;
        }
    }
    cout << ans << endl;
    return 0;
}