#include <bits/stdc++.h>
using namespace std;
int main() {
  string a;
  cin >> a;
  int r = 0, b = 0;
  for (int i = 0; i < a.size(); ++i) {
    if (a[i] == 'R') {
      r += 1;
    } else {
      b += 1;
    }
  }
  if (r > b) {
    cout << "Yes" << endl;
  } else {
    cout << "No" << endl;
  }
  return 0;
}
