#include <iostream>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n); i++)

int main(){
    string s; cin >> s;
    int n; n = s.size();
    int nh = 1;

    rep(i,n){
        if(s[i]=='R'){ nh = nh * 2 + 1; }
        else if(s[i]=='L'){ nh = nh * 2; }
    }
    cout << nh << endl;
    return 0;
}