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<?php class Database { private static $database; private function __construct() { // Nothing } public static function getInstance() { if (!self::$database) { self::$database = new Database(); } return self::$database; } } class BasicMath { public static function add($number1, $number2) { return $number1 + $number2; } } var_dump(BasicMath::add(1, 2));

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26.79 ms | 402 KiB | 5 Q