public void UndoCommands(int nbUndos)
 {
     Console.WriteLine("Undo commands.");
     while (nbUndos > 0 && m_undoStack.Count > 0)
     {
         RobotCommandBase command = m_undoStack.Pop();
         command.Undo();
         nbUndos--;
     }
 }
 public void ExcuteCommands()
 {
     Console.WriteLine("Excute commands.");
     while (Commmands.Count > 0)
     {
         RobotCommandBase command = Commmands.Dequeue();
         command.Excute();
         m_undoStack.Push(command);
     }
 }