private static boolean endsWithDoubleConsonent(String str) {
    char c = str.charAt(str.length() - 1);
    if (str.length() > 1 && c == str.charAt(str.length() - 2)) {
      return !containsVowel(str.substring(str.length() - 2));
    }
    return false;
  }
private static boolean endsWithDoubleConsonent(String str)