Yet, my perl issue is that I really wonder what would be a shorter solution for my longest_words routine.

I think you want to do the hash the other way around. I.e. make it a hash of lengths and push each word onto an anonymous array of words of than length:

sub longest_words {
    my %W;
    push (@{$W{length($_)}}, $_) for (split /\s+/, join ' ', @_);
    return @{$W{ (sort{$b <=>$a} keys %W)[0]} };
}
[download]

Notes: If you do a print Dumper (\%W); before the return you will see the hash that has been constructed.
The (sort{$b <=>$a} keys %W)[0] returns the key with the highest numerical value.

Dingus

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