阅读下列说明和C++代码，回答问题，将答案填入相应横线处。【说明】某实验室欲建立一个实验室环境监测系统，能够显示实验室的温度、湿度以及洁净度等环境数据。当获取到最新的环境测量数据时，显示的环境数据能够更新现在采用观察者(observer)模式来开发该系统，观察者模式的类图如下图所示。



?【C++代码】#include #include using namespace std;class Observer {public:????virtual void update(float temp, float humidity, float cleanness)=0;};class Subject {public:????virtual void registerObserver(Observer* o) = 0; //注册对主题感兴趣的观察者????virtual void removeObserver(Observer* o) = 0; //删除观察者????virtual void notifyObservers() = 0;//当主题发生变化时通知观察者};class EnvironmentData : public?????（1） ????{private:vector observers;float temperature, humidity, cleanness;public:????void registerObserver(Observer* o) { observers.push_back(o); }????void removeObserver(Observer* o) { /* 代码省略 */ }????void notifyObservers() {for(vector::const_iterator it = observers.begin(); ???????????it != observers.end(); it++){???????（2） ???; }}Void measurementsChanged() {?????（3） ???; }void setMeasurements(float temperature, float humidity, float cleanness) {????this->temperature = temperature;????this->humidity = humidity;????this->cleanness = cleanness;????????（4） ???;????}};class CurrentConditionsDisplay : public?????（5） ???{private: ?????float temperature, humidity, cleanness;????Subject* envData;public:????CurrentConditionsDisplay(Subject* envData) {????????this->envData = envData;???????????（6） ??; ??????}void update(float temperature, float humidity, float cleanness) ?{this->temperature = temperature;????this->humidity = humidity;????this->cleanness = cleanness;????display();}void display() { /* 代码省略 */ }};int main() {????EnvironmentData* envData = new EnvironmentData();????CurrentConditionsDisplay* currentDisplay = new CurrentConditionsDisplay(envData);????envData->setMeasurements(80, 65, 30.4f);????return 0;}