#include #define rep(i,n) for(int i = 0; i < (n); ++i) #define srep(i,s,t) for (int i = s; i < t; ++i) #define drep(i,n) for(int i = (n)-1; i >= 0; --i) using namespace std; typedef long long int ll; typedef pair P; #define yn {puts("Yes");}else{puts("No");} #define MAX_N 200005 int main() { string s; cin >> s; int n = s.size(); ll ans = 1; rep(i,n){ if(s[i] == 'L'){ ans = ans * 2; }else{ ans = ans * 2 + 1; } } cout << ans << endl; return 0; }