#include <bits/stdc++.h>
#define rep(i,n)for(long long i=0;i<(n);i++)
using namespace std;
typedef unsigned long long ull;
typedef long long ll;
const ll INF=1e18;
const int MOD=1e9+7;

const double pi=acos(-1);

int main(){
  ll ans=1;
  string s;
  cin >> s;
  rep(i,s.size()){
    if(s[i]=='L')ans=2*ans;
    else ans=2*ans+1;
  }
  cout << ans << endl;
}