public function seedSubClassSubject()
 {
     $drafts = Draft::all();
     foreach ($drafts as $index => $draft) {
         $teacher_name = trim($draft->teacher);
         $email = str_slug($teacher_name) . '@vnu.edu.vn';
         $teacher = User::all()->where('email', $email)->first();
         $teacher_id = $teacher->id;
         $tietX = $draft->tiet;
         $arr = explode('-', $tietX);
         if (count($arr) == 2) {
             $t_begin = intval($arr[0]);
             $t_end = intval($arr[1]);
             $thu = intval($draft->thu);
             $viTri = ($thu - 2) * 10 + $t_begin;
             $soTiet = $t_end - $t_begin + 1;
             $nhom_X = $draft->note;
             $nhom = 0;
             if (strtolower($nhom_X) == 'n1') {
                 $nhom = 1;
             }
             if (strtolower($nhom_X) == 'n2') {
                 $nhom = 2;
             }
             if (strtolower($nhom_X) == 'n3') {
                 $nhom = 3;
             }
             $classSubject = ClassSubject::all()->where('maLMH', $draft->maLMH)->first();
             $sub = SubClassSubject::create(['teacher' => $teacher_id, 'address' => trim($draft->address), 'viTri' => intval($viTri), 'soTiet' => intval($soTiet), 'soSV' => intval($draft->soSV), 'classSubject' => intval($classSubject->id), 'nhom' => intval($nhom)]);
             var_dump($index);
         }
     }
 }