3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = [ "https://i.imgur.com/vyGHgZN.jpg" => "dummy2", "https://i.imgur.com/UYK4Agz.png" => "dummy", "https://i.imgur.com/xEXdKYn.jpg" => "dummy", ]; $result = []; foreach ($arr as $key => $value) { $result[$value][] = $key; } print_r($result);

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