#include <bits/stdc++.h>
#define fastIO (cin.tie(0), cout.tie(0), ios::sync_with_stdio(false))
#define precise(i) fixed << setprecision(i)
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
using namespace std;

int left(int i) { return 2 * i; }
int right(int i) { return 2 * i + 1; }

int main() {
  fastIO;

  string s;
  cin >> s;

  int road = 1;
  for (const auto ch : s) {
    road = (ch == 'L' ? left(road) : right(road));
  }

  cout << road << '\n';
}