3v4l.org

run code in 300+ PHP versions simultaneously
<?php function x($n) { for($i = 1; $i <= $n; $i++) { $n % $i == 0 && $i != $n ? $factors[]=$i & $i!=$n : 0; } array_sum($factors) == $n ? printf('P') : printf('I'); } x(28);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
I
preferences:
298.57 ms | 405 KiB | 456 Q