PHP ʖ²ἯTH º󍋼/A Ղ 13. º¯ʽ ·µ»ؖµ function square ($num) {return $num * $num;} echo square (4); // outputs '16'. function small_numbers() {return array (0, 1, 2);} list ($zero, $one, $two) = small_numbers(); function returns_reference() {return $someref;} $newref = returns_reference(); º󍋼/A ưµ㼯A ɏһ¼¶