#include <bits/stdc++.h>
using namespace std;
int main() {
  string str;
  cin >> str;
  int red = 0, blue = 0;
  for (int i = 0; i < str.length(); i++) {
    if (str[i] == 'R')
      red++;
    else
      blue++;
  }
  if (red > blue)
    cout << "Yes";
  else
    cout << "No";
}
