#coding: UTF-8

import sys
import re
import itertools
from math import sqrt
from collections import deque

### defs ###

### main ###
S = sys.stdin.readline().strip('\r\n')
ans=1
move = {}
move['L'] = lambda x:x*2
move['R'] = lambda x:x*2+1
for c in S:
	ans = move[c](ans)
print(ans)