So... you want to tell whether or not a string is composed entirely of the alphabet a-z? That's pretty easy with a regexp. 
if ($string =~ /^[a-z]+$/) {
    print "Valid\n";
} else {
    print "Invalid\n";
}

[download]
You mentioned finite automata in your subject line, though. Am I missing something else here? ;)

Cheers,
Paul

In reply to Re: finite automata by pjf
in thread finite automata by Anonymous Monk

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