<?php
@ob_start();
@session_start();
$dizi = array('a', 'b', 'c', 'd');
$number = isset($_SESSION['say']) ? $_SESSION['say'] : 0 ;
$number = $number < count($dizi) ? $number : 0 ;
echo $dizi[$number];
$_SESSION['say'] = $number+1;
?>

<?php
$alpha = array('a', 'b', 'c', 'd', 'e', 'f', 'g');
$count = 0;

if (!isset($_COOKIE['count'])) {
setcookie('count', $count);
}
else {
$count = $_COOKIE['count'] + 1;
setcookie('count', $count);
}

echo $alpha[$count%count($alpha)];
?>