public function store(Request $request, $lecture_id, $subject_id)
{
$this->validate($request, ['title' => 'required', 'description' => 'required']);
$subject = Subject::find($subject_id);
Log::info('$subject_id: ' . $subject->title);
$topic = new Topic();
$topic->title = $request->title;
$topic->description = $request->description;
$topic->topic_content = $request->topic_content;
$topic->subject()->associate($subject);
$topic->save();
return redirect('/lectures/' . $lecture_id . '/subjects/' . $subject_id . '/topics');
}
