while (my $row= $csv->getline_hr($fh))
{
        $linecounter++;
        my $ip=$row->{'Source address'};
        my $url=$row->{'URL/Filename'};

        push @{ $ipURL{$ip} }, $url;

        if (!($linecounter % 50000))
        {
                print "Lines: $linecounter\n";
        }
}
        formatOutput(\%ipURL);
#       print Dumper \%ipURL;