working with vectors and class

Person.cpp

#include <iostream>
#include <string>
#include "Person.h"

Person::Person (std::string n, std::string a, int ag, int cn)
{
    std::cout << "the object is created " << std::endl;

    name = n;
    address = a;
    age = ag;
    contact_no = cn;
}

Person::~Person ()
{
    std::cout << "the object is destroyed " << std::endl;
}

std::string Person::display_name ()
{
    return this->name;
}

std::string Person::display_address ()
{
    return this->address;
}

int Person::display_age ()
{
    return this->age;
}

int Person::display_contact_no ()
{
    return this->contact_no;
}

void display (Person &obj)
{
    std::cout << obj.name << std::endl
              << obj.address << std::endl
              << obj.age << std::endl
              << obj.contact_no << std::endl;
}

Person.h

#ifndef PERSON_H
#define PERSON_H

#include <string>
#include <iostream>

class Person
{
    friend void display (Person &);


    public:
        Person (std::string, std::string, int, int );
        ~Person ();

        std::string display_name ();
        std::string display_address ();
        int display_age ();
        int display_contact_no ();

    private:
        std::string name, address;
        int age, contact_no;
};

#endif // PERSON_H

vec_class.cpp

#include <iostream>
#include "Person.h"
#include <vector>

int main()
{
    std::vector <Person> vec;

    vec.push_back ({"kryssel tillada", "las pinas city", 16, 222222});
    vec.push_back ({"mikael t de leon", "las pinas city", 14, 2222331});

    std::cout << std::endl;

    for (std::vector<Person>::iterator it = vec.begin(); it != vec.end(); ++it) {
        display(*it);
    }

    std::cout << std::endl;


    return 0;
}