#include<stdio.h>
#include<string.h>

int main()
{
  int kokudou=1;
  char c[31];
  int i;
  scanf("%s",c);
  for(i=0;i<strlen(c);i++){
    if(c[i]=='L'){
      kokudou = kokudou*2;
    }
    else{
      kokudou = kokudou*2 +1;
    }
  }
  printf("%d\n",kokudou);
  return 0;
}