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Metoda push() dodaje element do tablicy ale także zwraca jej długość, dlatego zapis
robi 2 rzeczy
- dodaje na końcu tablicy 2 liczby - 33 i 44,
- zwraca - nową aktualną długość tablicy i przypisuje ją do zmmiennej dane.
const tablica = [5,12,17,23,123,45,54];