3v4l.org

run code in 300+ PHP versions simultaneously
<?php function id($n=6) { $c = 'abcdefghijklmnopqrstuvwxyz0123456789'; for ($x=0,$r=null;$x<$n;$x++) { $r .= $c[mt_rand(0, strlen($c) - 1)]; } return $r; } echo id(11);

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36.15 ms | 402 KiB | 5 Q