3v4l.org

run code in 300+ PHP versions simultaneously
<?php $first = ['01-1970' => 0.00, '03-2019' => 4350.00, '05-2019' => 150.00, '06-2019' => 50.00]; $second = ['03-2019' => 0.00, '04-2019' => 0.00, '06-2019' => 34.83]; $result = []; foreach ([$first, $second] as $a) { foreach ($a as $k=>$v) { if (!isset($result[$k])) $result[$k] = 0; $result[$k] += $v; } } print_r($result);

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15.44 ms | 402 KiB | 5 Q