#include <bits/stdc++.h>
using namespace std;
const int mod = 1000000007;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  string s;
  cin >> s;
  int cnt = 0, n = s.size();
  for (int i = 0; i < (n); ++i)
    if (s.at(i) == 'R') cnt++;
  if (cnt > n - cnt)
    cout << "Yes" << endl;
  else
    cout << "No" << endl;
}
