3v4l.org

run code in 300+ PHP versions simultaneously
<?php $z = "hejsanhejsan";//$argv[1]; $x = str_split($z, 5); $l = "ABCDEFGHIJKLMNOPQRSTUVWXYZ012345"; foreach ($x as $y) { foreach (str_split(strrev($y)) as $a => $w) { $y[$a] = ctype_upper($w); } $z .= $l[bindec($y)]; } echo $z; var_dump(str_split(strrev($y)));

preferences:
56.14 ms | 402 KiB | 5 Q