Okay, in preparing for my competition tomorrow, i'm doing some practice problems from the previous years. One problem has me printing a diamond of '@'s in the center of the screen using only 3 print commands. I decided to take it a step further and write it using only one print, but in the midst of writing it, I seem to have not been able to get the Text::Autoformat module to work for me. Can anyone troubleshoot this?

use strict;
use warnings;
use Text::Autoformat;
my @array=qw/@/;
for my $i(1..10){
    @array = autoformat (@array, { justify => 'center' });
    print "@array\n";
    ((push @array, '@') x 2) if scalar(@array) < 10;
    ((pop @array) x 2) if scalar(@array) >= 10;
}
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One might also make not of the fact that I am shooting in the dark when it comes to doubling a command, haha.
Thanks!