排序（对象矢量）

Question

我是C ++的新程序员，我遇到了一个问题：

我有这堂课：

class car{
public:
    //Default Constructor
    car();

    //Overload Constructor
    car(string, int, float, float);

    //Desctructor
    ~car();

    //Access Functions
    string getbrand() const;
    int getyear() const;
    float getkm() const;
    float getprice() const;

    //Mutator Functions
    void setbrand(string);
    void setyear(int);
    void setkm(float);
    void setprice(float);

private:
    //variables
    string newbrand;
    int newyear;
    float newkm;
    float newprice;


};

//访问函数

string car::getbrand() const{
    return newbrand;
}

int car::getyear() const{
    return newyear;
}

float car::getkm() const{
    return newkm;
}

float car::getprice() const{
    return newprice;
}

所以，一旦我开始插入我的车，我就把它们放在一个矢量中：

void fillvector(vector<car>& newmyfleet){

    string brand;
    int year;
    float km;
    float price;

    cout << "How many cars do you want in your fleet? ";
    int fleetsize;
    cin >> fleetsize;

    for (int i = 0; i < fleetsize; i++){

        cout << "Car Brand: ";
        cin >> brand;

        cout << "Car Year: ";
        cin >> year;

        cout << "Car Kms: ";
        cin >> km;

        cout << "Car Price: ";
        cin >> price;

        car newcar(brand, year, km, price);
        newmyfleet.push_back(newcar);
        cout << endl;
    }

    cout << endl;
}

---

所以我的问题是这样的：我如何按照矢量，按品牌对我的所有汽车进行分类？!! 我尝试过使用排序，但我不能......

这是我的最后一个解决方案：

//功能1

bool sortbybrand(car &c1, car &c2) { return c1.getbrand() < c2.getbrand(); }

//排序

void sbrand(const vector<car>& newmyfleet){

    unsigned int size = newmyfleet.size(); //Number of cars

    sort(newmyfleet.begin(), newmyfleet.end(), sortbybrand);

    cout << "Sorting Cars by Brand\n\n " << endl;

    for (unsigned int i = 0; i < size; i++){
            cout << "Car: " << i + 1 << endl;
            cout << "Car Brand: " << newmyfleet[i].getbrand() << endl;
            cout << "Car Year: " << newmyfleet[i].getyear() << endl;
            cout << "Car Kms: " << newmyfleet[i].getkm() << endl;
            cout << "Car Price: " << newmyfleet[i].getprice() << endl;
            cout << endl;
    }

}