- var_dump: documentation ( source)
- array_walk_recursive: documentation ( source)
<?php
$array = [
1 => [
1 => [
'anna',
'alice'
],
2 => [
'bob',
'bartold'
]
],
2 => [
1 => [
'carol'
],
2 => [
'david'
]
]
];
$result = [];
array_walk_recursive($array, function ($value, $key) use (&$result) {
if (!is_array($value)) {
$result[] = $value;
}
});
var_dump($result);