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<?php $A = ["EUR"=>10, "USD"=>20]; $B = ["EUR"=>10, "JPY"=>20]; $result = $A; foreach ($B as $k => $v) { $result[$k] = ($result[$k] ?? 0) + $v; } var_export($result);
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
array ( 'EUR' => 20, 'USD' => 20, 'JPY' => 20, )
preferences:
101.9 ms | 402 KiB | 62 Q