#include<iostream>
#include<string>
#include<string.h>
#include<algorithm>
#include<stdio.h>
#include<cmath>
#include<vector>
#include<utility>
#include<stack>
#include<queue>
#include<list>
#include<bitset>

#define FOR(i, a, b) for(int i=(a);i<=(b);i++)
#define RFOR(i, a, b) for(int i=(a);i>=(b);i--)
#define MOD 1000000007
#define INF 1000000000

using namespace std;


int main(void) {
	char s[35];
	int pos = 1;
	int p;

	fgets(s,34,stdin);
	FOR(i, 0, 31) {
		if (s[i] == '\0') {
			p = i;
			break;
		}
	}
	FOR(i, 0,p-2) {
		if (s[i] == 'L') {
			pos = pos * 2;
		}
		else {
			pos = pos * 2 + 1;
		}
	}
	cout<<pos<<endl;
	return 0;
}