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num =


Fatal error: Uncaught TypeError: sort(): Argument #1 ($array) must be of type array, null given in B:\xampp\htdocs\dongseo.vip\webprogramming20251\homework3-2.php:17 Stack trace: #0 B:\xampp\htdocs\dongseo.vip\webprogramming20251\homework3-2.php(17): sort(NULL) #1 {main} thrown in B:\xampp\htdocs\dongseo.vip\webprogramming20251\homework3-2.php on line 17