3v4l.org

run code in 300+ PHP versions simultaneously
<?php $count = 5; $last = 4; foreach (range(-5, 4, 1) as $v) { if ($v < 0) { print $v . ': ' .$v % $count . ' ' . ((($v % $count) + $count) % $count + 1) . "\n"; } else { print $v . ': ' .$v % $count . ' ' . (($v % $count) + $count) % $count . "\n"; } }

preferences:
39.89 ms | 402 KiB | 5 Q