#include <stdio.h>

int main(){
  char s[30];
  int route = 1;
  int i;
  char c;
  int j = 0;
  for(i = 0; (c = getchar()) != '\n'; i++) {
  	s[i] = c;
    j ++;
  }

 for(i = 0; i < j; i++){
    if(s[i] == 'L'){
      route *= 2;
    }else{
      route *= 2;
      route += 1;
    }
  }

  printf("%d\n", route);
  return 0;
}