Should I choose the label or other ui object before runtime? Can I choose them on runtime?

What I mean is :

Should I write:
Qt Code:
  1. for (int i = 0; i < 5 ; i++)
  2. {
  3. ui->label_0->setText(QString::number(i));
  4. ui->label_1->setText(QString::number(i));
  5. ui->label_2->setText(QString::number(i));
  6. ui->label_3->setText(QString::number(i));
  7. ui->label_4->setText(QString::number(i));
  8.  
  9. }
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But I want to write as:

Qt Code:
  1. for (int i = 0; i < 5 ; i++)
  2. {
  3. ui->label_(i)->setText(QString::number(i));
  4.  
  5. }
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Is it possible to write in this way?