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<?php $arr1 = [ "Friday" => ["Breakfast" => 32, "Lunch" => 45], "Sunday" => ["Lunch" => 12] ]; $arr2 = [ "Sunday" => ["Breakfast" => 7, "Lunch" => 3], "Monday" => ["Breakfast" => 12] ]; $arr3 = [ "Monday" => ["Breakfast" => 31] ]; $result = []; foreach (array_merge_recursive($arr1, $arr2, $arr3) as $day => $meals) { foreach ($meals as $meal => $counts) { $result[$day][$meal] = array_sum((array)$counts); } } var_export($result);
Output for 5.6.40, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
array ( 'Friday' => array ( 'Breakfast' => 32, 'Lunch' => 45, ), 'Sunday' => array ( 'Lunch' => 15, 'Breakfast' => 7, ), 'Monday' => array ( 'Breakfast' => 43, ), )
preferences:
137.42 ms | 407 KiB | 5 Q