"I noticed that some of you are using Perl 6... I think 'say is Perl 6?"

It can be Perl 6, but it is also Perl 5, for any version of Perl from December 2007, onward (Perl 5.10 or newer). The key is to enable that keyword using the feature pragma:

use feature 'say';
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Or to enable groups of features for a given Perl version by using feature bundles or specifying a Perl version number (again, see feature for an explanation).

At any rate, none of the examples I've seen so far are in Perl 6. Unless someone submits a Perl 6 solution after I post this, all of the solutions here should all work with DWIM Perl, or any other modern version of Perl.