#include <bits/stdc++.h>
#define rep(i, a, n) for(int i = a; i < n; i++)
#define repp(i, n) rep(i, 0, n)
#define repb(i, a, b) for(int i = a; i >= b; i--)
#define all(a) a.begin(), a.end()
#define int long long
using namespace std;

//yuki104

signed main(){
    string s;
    cin >> s;
    int ans = 1;
    rep(i, 0, s.size()){
        if(s[i] == 'L') ans *= 2;
        else ans = ans * 2 + 1;
    }
    cout << ans << endl;
}