3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $array = [ 1 => [ 1 => [ 'anna', 'alice' ], 2 => [ 'bob', 'bartold' ] ], 2 => [ 1 => [ 'carol' ], 2 => [ 'david' ] ] ]; $result = []; $prevKey = 0; array_walk_recursive($array, function ($value, $key) use (&$result, &$prevKey) { if (!is_array($value)) { }else { $prevKey = $key; echo $prevKey; } }); var_dump($result);
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