#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int a = 0, b = 0;
  string s;
  cin >> s;
  for (auto ch : s) {
    if (ch == 'R') {
      a++;
    } else {
      b++;
    }
  }
  if (a > b) {
    cout << "Yes" << '\n';
  } else {
    cout << "No" << '\n';
  }
  return 0;
}
