Recursive functions

<?php
function printValues ($arr) {
global $count;
global $out;
if (!is_array($arr)) {
die ('ERROR: Input is not an array');
}
foreach ($arr as $a) {
if (is_array($a)) {
printValues ($a);
} else {
$out [] = $a;
$count++;
}
}
return array ('total' => $count, 'values' => $out);
}
$data = array( 'o' => array('orange','owl','one'), 't' => array('tea', 'ten', 'tag', 'twentythree' => array(array('twenty', 'three'), array('vingt', 'trois', array('red' => 'baron', 'blue' => 'blood')))));
$ret = printValues ($data);
echo $ret['total'] . ' value(s) found: ';
echo implode (',', $ret['values']);
?>