use Data::Dumper;
use List::Util 'shuffle';

# randomized list
my @a1 = shuffle ( '1,5', '3,9', '3,4', '6,2', '8,1' );
# convert to an array of hashes 
my @a2 = map { s/,/,y,/; s/\A/x,/; +{ split /,/ } } @a1;
# sort 'x' values ascending and 'y' values descending
my @a3 = sort { $a->{x} <=> $b->{x} || $b->{y} <=> $a->{y} } @a2;
print Dumper \@a3;
__END__
$VAR1 = [
          {
            'y' => '5',
            'x' => 1
          },
          {
            'y' => 9,
            'x' => 3
          },
          {
            'y' => 4,
            'x' => 3
          },
          {
            'y' => '2',
            'x' => 6
          },
          {
            'y' => '1',
            'x' => 8
          }
        ];