in reply to
words wich ends with "f"
I'd go with something like this (yeah, TIMTOWTDI):
$s = "four fifth two frog left leaf fred wolf";
@f = grep (/^[^f]\w*f\w*$/, split(' ', $s));
By rote learning.
Via Genetic memory.
It's provided by my firmware.
I just remember them.
Thirty days hath September
My computer gets it right, usually.
I just ask someone else.
Someone punches me on the first of the month.
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