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Pętla for jak śnieżna kula ulepi kod HTML, zwiększając go w każdym
obrocie o kolejną liczbę od 1 do 100 i przecinek (,).
Kod HTML czyli zmienna kodHTML zostanie wstrzykniety do div-a wynik
Operator += pozwala uprościć zapis, zapis:
kodHTML+=i+', '; jest równoznaczny zapisowi kodHTML=kodHTML+i+', ';
//utworzenie zmiennej, która będzie przechowywać kod do wstrzyknięcia