Online PHP editor | refs for 9gCH1

<?php $array = [ 8 => [ 2 => [ 'num_rooms' => 2, 'adults' => [1, 1], 'children' => [0, 0], 'prices' => [50, 50], 'price' => 130, 'supp' => 30, ], 3 => [ 'num_rooms' => 1, 'adults' => [1], 'prices' => [100], 'price' => 150, 'supp' => 50, ], ], 1 => [ 2 => [ 'num_rooms' => 2, 'adults' => [1, 1], 'children' => [1, 0], 'prices' => [75, 75], 'price' => 170, 'supp' => 20, ], ], ]; $result = []; foreach (array_merge(...$array) as $row) { foreach ($row as $k => $v) { $result[$k] = ($result[$k] ?? 0) + array_sum((array) $v); } } var_export($result);