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run code in 300+ PHP versions simultaneously
<?php $main = [ 'lorem' => 'lorem', 'ipsum' => 'duis', 'sit' => 'adipiscing', 'duis' => 'sit', 'amet' => 'elit', 'consectetur' => 'lorem', 'adipiscing' => 'consectetur', 'eiusmod' => 'ipsum', 'labore' => 'eiusmod', 'dolore' => 'labore', 'magna' => 'dolore', 'aliqua' => 'amet', 'incididunt' => 'magna', 'tempor' => 'incididunt', 'sed' => 'tempor', 'elit' => 'sed', ]; foreach ($main as $k => $v) { if ($k === $v) { $result[$k] = $v; } else { $map[$v] = $k; } } foreach ($result as $key => &$val) { $result[$map[$key]] = $key; if ($main == $result) { break; } } var_export($result);

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