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run code in 300+ PHP versions simultaneously
<?php function x($n) { $z="printf"; for($i = 1; $i <= $n; $i++) { $n % $i == 0 && $i != $n ? $f[]=$i & $z('$i '): 0; } array_sum($f) == $n ? $z('P') : $z('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 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
$i $i $i $i $i I
preferences:
250.06 ms | 406 KiB | 356 Q