#include <stdio.h>
#include <algorithm>
#include <deque>
using namespace std;
using ll = long long;

//104
int main() {
	char s[31];
	int cur = 1, p = 0;
	while(true) {
		scanf("%c", s + p);
		if (s[p] == '\n')
			break;
		p++;
	}
	s[p] = 0;
	for (int i = 0; s[i] != 0; i++) {
		if (s[i] == 'L')
			cur = cur * 2;
		else
			cur = cur * 2 + 1;
	}
	printf("%d\n", cur);
}