Enthuware

Hello,

The last sentence of the last paragraph of the explanation is probably not for this question:

Observe that it does not remove all occurences of the element. It removes just the first one. In this case, only the first "a" will be removed.

There was only one "a" in the question and not that "a" was removed.

Not a big deal, but your questions/explanations have usually high quality.
Péter

You are right. That part must be removed.
thank you for your feedback!