public override void GiveAnswerToQuestion()
 {
     if (_successor == null)
     {
         Console.WriteLine("Middle programmer give answer on question");
     }
     else
     {
         _successor.GiveAnswerToQuestion();
     }
 }
 public virtual void GiveAnswerToQuestion()
 {
     if (_successor == null)
     {
         Console.WriteLine("I give answer on question");
     }
     else
     {
         _successor.GiveAnswerToQuestion();
     }
 }