array_pop() returns the last element of an array, at the same time delete the element from the array. If the array is empty, or the parameter is not an array, return NULL.

<?PHP
	$arr=array(1,2,3,4,5,6,7,8,9);
    $ret=array_pop($arr);
	echo "$ret";  //9
	foreach($arr as $element) echo "$element, ";  //1, 2, 3, 4, 5, 6, 7, 8,
?>

However, if the array is an associative array, only the value will be returned.

<?PHP
	$arr = array("one"=>"Monday","two"=>"Tuesday","three"=>"Wednesday",
	"four"=>"Thursday","five"=>"Friday","six"=>"Saturday","seven"=>"Sunday");

    $elem = array_pop($arr);
    echo "$elem";  //the result is Sunday
?>

The following code will return the last key, value pair of the specific associative array, and remove the last key, value pair from the array as well.

<?PHP
	$arr = array("one"=>"Monday","two"=>"Tuesday","three"=>"Wednesday",
	"four"=>"Thursday","five"=>"Friday","six"=>"Saturday","seven"=>"Sunday");

    $elempair = [array_key_last($arr) => array_pop($arr)];
?>