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

int main(void){
    
    int current_root = 1;
    char root_hist[31];
    char *p;
    
    scanf("%s", root_hist);
    
    p = root_hist;
    
    while(*p != '\0'){
        
        if(*p == 'L'){
            current_root = current_root*2;
        }
        if(*p == 'R'){
            current_root = current_root*2+1;
        }
        /* debug
        if(current_root == 114){
            printf("514");
        }
        if(current_root == 810){
            printf("1919");
        }
        */
        p++;
    }
    printf("%d\n", current_root);
}