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