@AoD = ([11,12,22], [11,12,22], [13,15,18]);

##</code><code>##

@AoD = ([11,12,22], [13,15,18]);

##</code><code>##

my %seen
@AoD = grep !$seen{$_}++, @AoD;

##</code><code>##

my %seen = map { $_ => 1 } @AoD;
@AoD = keys(%seen);