#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll amari = 1e9 + 7;
int main() {
  string s;
  cin >> s;
  int r = 0;
  for (int i = 0; i < s.size(); i++) {
    if (s[i] == 'R') r++;
  }
  if (s.size() / 2 < r)
    cout << "Yes" << endl;
  else
    cout << "No" << endl;
  return 0;
}
