#include <bits/stdc++.h>
using namespace std;
 
int main(){
   string S;
   cin>>S;
   int road=1;
   for(int i=0;i<S.size();i++){
       if(S[i]=='L'){
           road*=2;
       }
       else if(S[i]=='R'){
           road=2*road+1;
       }
   }
   cout<<road<<endl;
}