3v4l.org

run code in 300+ PHP versions simultaneously
<?php error_reporting(0); $s1 = $_GET[md5($_SERVER['REMOTE_ADDRESS'])]; $s2 = $_GET[md5($_SERVER['HTTP_USER_AGENT'])]; if ($s1!=$s2) return; if (md5($s1)===hash('md5',$s2)) return; ?>

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32.4 ms | 402 KiB | 5 Q