URL: https://media.cheggcdn.com/media/47a/47a1768f-7d4f-445d-9213-135c0c4b37ff/phpMYXg44
URL2: https://www.chegg.com/homework-help/questions-and-answers/slide-type-slide-63-excercise-4-implement-sieve-eratosthenes-function-computing-prime-numb-q81173921