- print_r: documentation ( source)
- max: documentation ( source)
- min: documentation ( source)
<?php
$array = array
(
24 => 24,
25 => 25,
26 => 26,
27 => 27,
28 => 28,
29 => 29,
);
$min = min($array) - 1;
$max = max($array) + 1;
$array[$min] = $min;
$array[$max] = $max;
print_r($array);