c++类导入，引发缺少类型说明符

Question

刚学c++primer第七章，发现类导入会引发缺少类型说明符，不知道该怎么改

#include <iostream>
#include "person.h"

using namespace std;

int main() {
    Person p1;
    return 0;
}

#ifndef PERSON_H
#define PERSON_H
#include <iostream>
#include <string>

class Person {
private:
    string strName;
    string strAddress;

public:
    string getName() const {
        return strName;
    }

    string getAddress() const {
        return strAddress;
    }

    istream& read(istream& is, Person per) {
        is >> per.strName >> per.strAddress;
        return is;
    }

    ostream& print(ostream& os, Person per) {
        os << per.getName() << per.getAddress();
        return os;
    }

};

#endif // !#PERSON_H

Answer 1

person.h文件中，加上命名空间

using namespace std;