#include <bits/stdc++.h>
using namespace std;
const double pi = acos(-1);
const long long mod = 1e9 + 7;
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  string s;
  long long rr = 0, bb = 0;
  cin >> s;
  for (char c : s) {
    rr += (c == 'R');
    bb += (c == 'B');
  }
  cout << (rr > bb ? "Yes" : "No");
  return 0;
}
