if (exists $db{$url}) {
my $value = $db{$url};

$value++;
$db{$url} = $value;

print "Location: $url\n\n";
}
else {
$db{$url} = 1;
print "Location: $url\n\n";
}

##</code><code>##

$db{ $url } ++;
print "Location: $url\n\n";