#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int r = 0, b = 0;
  for (auto c : s) {
    if (c == 'R')
      ++r;
    else
      ++b;
  }
  if (r > b)
    cout << "Yes" << endl;
  else
    cout << "No" << endl;
}
