No!
No downvote, but your regex misses the limit of 1 to 4 "f"s in OP's statement of the problem.
See FunkyMonk's prior reply (which <span class="pedantic picky)"> errs (albeit, in it's original form, and only marginally) in the comment at line 4:
{1,4} # between 1 & 4 of themonly insomuch as the set of integers between "1 & 4" includes only "2" and "3."</span>
Hmm... :-) maybe the "picky pedantic" tag should enclose this whole note....
In reply to Re^2: Regular expression for hexadecimal number
by ww
in thread Regular expression for hexadecimal number
by isha
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