                           cellForRowAt indexPath: IndexPath) -> UITableViewCell {
     let cell: UITableViewCell
 
-    switch (indexPath as NSIndexPath).section {
+    switch indexPath.section {
     case kSectionPost:
       cell = tableView.dequeueReusableCell(withIdentifier: "post")!
       if let uid = Auth.auth().currentUser?.uid {

  }

  override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    if (indexPath as NSIndexPath).section == kSectionPost {
      return 160
    }
    return 56

      }
    case kSectionComments:
      cell = tableView.dequeueReusableCell(withIdentifier: "comment")!
      let commentDict = comments[indexPath.row].value as? [String : AnyObject]
      if let text = cell.textLabel, let detail = cell.detailTextLabel,
        let author = commentDict?["author"], let commentText = commentDict?["text"] {
        detail.text = String(describing: author)
