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<?php function x($n) { for($i = 1; $i <= $n; $i++) { if ($n % $i == 0 && $i != $n) { $factors[] = $i; echo "$i "; } } return (array_sum($factors) == $n) ? printf("Perfect") : printf("[Imperfect]"); } x(42);
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, 5.5.24 - 5.5.35, 5.6.8 - 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
1 2 3 6 7 14 21 [Imperfect]

preferences:
201.51 ms | 405 KiB | 310 Q