#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;

#include <math.h>

int main() {
string s;
cin>>s;
int ans=1;
for (int i = 0; i < s.length(); ++i) {
	if(s[i]=='L'){
		ans=ans*2;
	}else{
		ans=ans*2+1;
	}
}
cout<<ans<<endl;


}