#include using namespace std; #define repl(i, l, r) for (ll i = (l); i < (r); i++) #define rep(i, n) repl(i, 0, n) #define CST(x) cout << fixed << setprecision(x) using ll = long long; const ll MOD = 1000000007; const int inf = 1e9 + 10; const ll INF = 4e18 + 10; const int dx[9] = {1, 0, -1, 0, 1, -1, -1, 1, 0}; const int dy[9] = {0, 1, 0, -1, 1, 1, -1, -1, 0}; int main() { cin.tie(0); cout.tie(0); ios::sync_with_stdio(false); string s; cin >> s; ll ans = 1; for (auto c : s) { ans *= 2; if (c == 'R') ans++; } cout << ans << endl; return 0; }