#include <cstdio>
int main()
{
    char s[100];
    while (fgets(s, 100, stdin)) {
        unsigned res=1;
        for(int i=0;s[i]>'A';++i) {
            res*=2;
            if (s[i]=='R') ++res;
        }
        printf("%u\n", res);
    }
}