#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int red = 0, blue = 0;
  for (int i = 0; i < s.size(); ++i) {
    if (s[i] == 'R')
      ++red;
    else
      ++blue;
  }
  if (red > blue)
    cout << "Yes" << endl;
  else
    cout << "No" << endl;
  return 0;
}
