#include <bits/stdc++.h>
using namespace std;
long long int M = 1e5;
int main() {
  string s;
  cin >> s;
  long long int len = s.length();
  long long int r = 0, b = 0;
  for (long long int i = 0; i < len; i++) {
    if (s[i] == 'R')
      r++;
    else
      b++;
  }
  if (r > b) {
    cout << "Yes" << endl;
  } else {
    cout << "No" << endl;
  }
}
