#!/usr/bin/env perl -l

use strict;
use warnings;

my @AoA = (
    [ 2, 13, 3, 16 ],
    [ 10, 1, 11, 6 ],
    [ 0, 10, 11, 19 ],
    [ 6, 1, 19, 15 ],
    [ 17, 6, 18, 12 ],
);

my $selected = $AoA[2];
my %unique = map { $_ => 1 } @$selected;

print "@$_" for grep { ! map { $_ ? $_ : () } @unique{@$_} } @AoA;

##</code><code>##

2 13 3 16
17 6 18 12