use Data::Dumper;
my (@c, @d);

foreach (1..3) {
  @c[0..4] = (rand) x 2;
  push @d, \@c;
}
print Dumper \@d;

@d=();  ## reset @d
foreach (1..3) {
  @c[0..4] = (rand) x 2;
  push @d, [@c];
}
print Dumper \@d;
__END__
$VAR1 = [
          [
            '0.566846394018409',
            '0.566846394018409'
          ],
          $VAR1->[0],
          $VAR1->[0]
        ];
$VAR1 = [
          [
            '0.872105763616624',
            '0.872105763616624'
          ],
          [
            '0.0550789852978433',
            '0.0550789852978433'
          ],
          [
            '0.130973801235072',
            '0.130973801235072'
          ]
        ];