#include <bits/stdc++.h>

using namespace std;

const double PI = acos(-1);

int main()
{
  string S;
  cin >> S;
  int ret = 1;
  for(char& c : S) {
    if(c == 'L') ret = ret * 2;
    else ret = ret * 2 + 1;
  }
  cout << ret << endl;
}