package main

import (
	"fmt"
)

func resolve(S string) int {
	ret := 1
	for _, c := range S {
		if c == 'L' {
			ret = ret * 2
		} else {
			ret = ret*2 + 1
		}
	}
	return ret
}

func main() {
	var S string
	fmt.Scanf("%s\n", &S)
	fmt.Println(resolve(S))
}