sub containsAll {
    my ($arrEverything, $arrRequire) = @_;
    my %stillRequired = map { $_ => 1 } @$arrRequire;
    for my $entry ( @$arrEverything ) {
        if ( delete($stillRequired{$entry}) ) {
            last unless %stillRequired;
        }
    }
    return %stillRequired ? 0 : 1;
}