#include<stdio.h>
main(){
    char S[31];
    int i;
    char c;
    for(i = 0;(c=getchar()) !='\n';i++){
        S[i] = c;
    }
    S[i] = '\0';
    int point = 1;
    for(i = 0;S[i] != '\0';i++){
        point = S[i]=='L'?point*2:point*2+1;
    }
    printf("%d\n",point);
}