Как сделать сортировку по полю ?И как сделать деструктор для данного класса?

#include <iostream>
#include <string>
using namespace std;
#pragma warning(disable: 4996)

class Computer
{
    string nazwanie;
    int model;
    int price;

public:
    friend bool operator> (const Computer& d1, const Computer& d2);
    friend bool operator<= (const Computer& d1, const Computer& d2);

    friend bool operator< (const Computer& d1, const Computer& d2);
    friend bool operator>= (const Computer& d1, const Computer& d2);
    Computer()
    {
        nazwanie;
        model = 0;
        price = 0;
    }

    Computer(string nazwanie, int model, int price)
    {
        this->nazwanie = nazwanie;
        this->model = model;
        this->price = price;
      
    }

    ~Computer()
    {
      
    }

    void vivod()
    {
        cout <<"Name of computer: "<< nazwanie<< ".Model number:"<< model << ".Price in $ : " << price << endl;
    }
};
bool operator> (const Computer& d1, const Computer& d2)
{
    return d1.price > d2.price;
}

bool operator>= (const Computer& d1, const Computer& d2)
{
    return d1.price >= d2.price;
}

bool operator< (const Computer& d1, const Computer& d2)
{
    return d1.price < d2.price;
}

bool operator<= (const Computer& d1, const Computer& d2)
{
    return d1.price <= d2.price;
}
int main()
{
    Computer p1("Dell", 349, 1024);
    Computer p2("Asus", 1231, 2000);
    Computer p2("Samsung", 1080, 1500);

    p1.vivod();
    p2.vivod();
    if (p1 < p2)
        cout << "Asus is more expensive then Dell"<<endl;



    return 0;
}