ZEND PHP 5 Certification STUDY GUIDE

Arrays ” 67
$keys = array_rand ($cards, 2);
var_dump ($keys);
var_dump ($cards);
If you run the script above, its output will look something like this:
array(2) {
[0]=>
string(1) "a"
[1]=>
string(1) "b"
}
array(3) {
["a"]=>
int(10)
["b"]=>
int(12)
["c"]=>
int(13)
}
As you can see, extracting the keys from the array does not remove the corresponding
element from it—something you will have to do manually if you don’t want to extract
the same key more than once.
Arrays as Stacks, Queues and Sets
Arrays are often used as stacks (Last In, First Out, or LIFO) and queue (First In, First
Out, or FIFO) structures. PHP simplifies this approach by providing a set of functions
can be used to push and pop (for stacks) and shift and unshift (for queues) elements
from an array.
We’ll take a look at stacks first:
Licensed to 482634 - Amber Barrow (itsadmin@deakin.edu.au)
$stack = array();
array_push($stack, ’bar’, ’baz’);
var_dump($stack);