#define _USE_MATH_DEFINES
#include<stdio.h>
#include<string>
#include<iostream>
#include<cctype>
#include<cstdio>
#include<vector>
#include<stack>
#include <algorithm>
#include<math.h>
#include<set>
#include<map>
#include<iomanip>
//#include<bits/stdc++.h>


using namespace std;




int main() {
  

	string p;
	long long int t=1;
	cin>>p;
	for(int i=0;i<p.size();i++){
		if(p[i]=='L')t=t*2;
		else t=t*2+1;
	}
	cout<<t<<endl;

    return 0;
}