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<?php $a1 = [ "a" => 2, "b" => 0, "c" => 5, ]; $a2 = [ "a" => 3, "b" => 9, "c" => 7, "d" => 10, ]; var_export( array_reduce( array_keys($a2), fn($result, $k) => array_merge($result, [$k => ($result[$k] ?? 0) + $a2[$k]]), $a1 ) );
Output for 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array ( 'a' => 5, 'b' => 9, 'c' => 12, 'd' => 10, )
preferences:
75.03 ms | 988 KiB | 4 Q