#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  string s;
  cin >> s;
  int cnt = 0;
  for (auto c : s) {
    if (c == 'R') {
      cnt++;
    }
  }
  if (cnt > s.length() - cnt) {
    cout << "Yes";
  } else {
    cout << "No";
  }
  return 0;
}
