3v4l.org

run code in 300+ PHP versions simultaneously
<?php $data = [ 9 => [ 1 => [2 => 433, 6 => 2, 4 => 101], 3 => [6 => 999], ], 14 => [ 2 => [2 => 0, 6 => 2], ] ]; $result = array_map(fn($v) => array_sum(array_map(fn($v) => array_sum($v), $v)), $data); print_r($result);

preferences:
25.45 ms | 406 KiB | 5 Q