3v4l.org

run code in 300+ PHP versions simultaneously
<?php define("EOL", "\n"); $max = 40; $start = ord("a"); $limit = ord("y"); $arr = array(); $arr[0] = chr($start); while($max--){ for($i = 0; $i <= (count($arr) - 1); $i++){ if(ord($arr[$i]) > $limit){ $arr[$i] = chr($start); if(isset($arr[$i + 1])){ $arr[$i+1] = chr(ord($arr[$i+1]) + 1); } else { $arr[$i+1] = chr($start); } } } var_dump(array_reverse($arr)); echo "[", implode("][", array_reverse($arr)), "]", EOL; $arr[0]++; }

preferences:
35.18 ms | 402 KiB | 5 Q