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