Stack
$stack = array();
$book_one = "One";
$book_two = "Two";
$book_three = "Three";
array_push($stack, $book_one);
array_push($stack, $book_three);
array_push($stack, $book_two);
$n = count ($stack);
while ($book = array_pop ($stack)) {
print ("Item $n: $book
$n--;
}
?>