how to make every other click on a link display a different link ?

[jjk2]

lets say i have a link.

 

i want it to display 2 URLS.

 

if i click it once, it will display google.com

 

if i click it the second time, it will display yahoo.com

 

how can i do this using cookie sessions ?

[marcus]

<?php
session_start();

print_r($_SESSION);

if($_SESSION['clicks'] >= 0){
$_SESSION['clicks'] += 1;
}else {
$_SESSION['clicks'] = 0;
}

$urls = array(0 => 'http://google.com', 1 => 'http://yahoo.com', 2 => 'http://msn.com', 3 => 'http://omgpie.com');

echo "<a href=\"".$urls[$_SESSION['clicks']]."\">".$urls[$_SESSION['clicks']]."</a>\n";
?>