public function lecture_pdf()
 {
     $rules = ['pdf' => 'required|mimes:pdf|max:2000'];
     $file = Input::only('pdf');
     $validator = Validator::make($file, $rules);
     if ($validator->fails()) {
         return Redirect::back()->withInput()->withErrors($validator);
     } else {
         $lecture = Lecture::findorFail(Input::get('id'));
         $destinationPath = 'pdf';
         $fileName = $lecture->id . '.' . 'pdf';
         Input::file('pdf')->move($destinationPath, $fileName);
         $lecture->pdf = $fileName;
         $lecture->save();
         Session::flash('pdf_edited', 'alt');
         return redirect::back();
     }
 }
 public function show($id)
 {
     $lecture = Lecture::findorFail($id);
     return view('pages.rogue', compact('lecture'));
 }