use strict;
use warnings;
use List::Util "reduce";
use Lingua::EN::Inflect "inflect";
use Algorithm::Loops "MapCar";

my @array = qw/A B C B D B D/;
print
map { map ( inflect("There PL(is,$_) $_ PL(element,$_) of "), $_->[1] 
+), "$_->[0]\n" }
MapCar { [@_] }
map { [sort keys %$_], [@$_{sort keys %$_}] }
reduce { $a->{$b||$b}++; $a } {},
@array
;
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Sometimes it amuses me to place arbitrary constraints on myself in answering a question. In this case, I decided I was limited to one statement and no (declared) variables other than the input.

Update: replaced an ugly reduce with MapCar.
Update: additional topicalization