#include <bits/stdc++.h>
using namespace std;
signed main() {
  string s;
  cin >> s;
  int64_t r = 0;
  int64_t b = 0;
  for (char c : s) {
    if (c == 'R')
      r++;
    else
      b++;
  }
  if (r > b)
    cout << "Yes" << endl;
  else
    cout << "No" << endl;
}
