The lazy way:

#!/usr/bin/perl -slw

use strict;
use warnings;
use Tie::Quicksort::Lazy TRIVIAL => 2;

my @end = qw/ 3 2 6 5 4 /;
my @sorted_input = sort @end;

tie my @sorted, 'Tie::Quicksort::Lazy', @end;
while (@sorted) {
    my $this = shift @sorted;
    print $this;
}
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