3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = [ ["2" => 6, "5" => 1], ["2" => 1, "5" => 3], ]; $result = []; foreach ($array as $row) { foreach ($row as $k => $v) { if (!isset($result[$k]) || $result[$k] < $v){ $result[$k] = $v; } } } var_export($result);

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30.18 ms | 404 KiB | 5 Q