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