I'm not sure about the meaning of this regular expression.
^[^a]*$
Does that mean, we don't want any string started with the letter a or contain a. And we don't want any string ended with also the letter a ?.
thanks.
^ asserts position at start of a line[^a] Match a single character not present in the list* Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy)$ asserts position at the end of a lineSo it will essentially match any line and does not contain an a