#include <stdio.h>

int main(void){
    char s[1000];
    scanf("%s",s);
    long long int ans = 1;
    if(s[0]=='\n'){printf("1\n");return 0;}
    for(int i=0;s[i]!='\n';i++){
        if(s[i]=='L'){ans = ans*2;}
        else{ans = ans*2+1;}
    }
    printf("%lld\n",ans);
    
}