Authentication

[JoshUK]

I wrote this script today, and it works with check the password and everything, but how do i get it to go to another webpage when the password is right?

<form name="form1" method="post" action="<?php $_SERVER['PHP_SELF']; ?>?action=login">
Username:<input type="text" name="u"><br>
Password:<input type="text" name="p"><br>
<input type="submit" name="Submit" value="Submit">
</form>
<?php
$server = "localhost";
$username = "root";
$password = "";
$datebase = "login";
$a = 0;

$db = mysql_connect($server, $username, $password);

mysql_select_db($datebase, $db);

$result = mysql_query("SELECT * FROM users WHERE username='$u'",$db) or die(mysql_error());



while ( $r = mysql_fetch_array( $result ) ) {
$uu = $r['username'];
$pp = $r['password'];

}

if (isset($action) && $action == 'login') {

if ($uu == $u && $pp == $p){
	echo "Right!";
	$a ++;
}else
	echo "Wrong!";
	$a == 0;

}
print $a;
?>

thanks for any help