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