Как я могу получить вектор одного класса для данных pu sh обратно из векторов в двух других классах?

Question

Учитывая классы A, B и C, я хотел бы знать, как я могу вернуть sh компоненты векторов, принадлежащих классам A и B, в один вектор, принадлежащий классу C.

Например, в следующем коде у меня есть простая программа для заказа пиццы. Программа позволяет пользователю вводить в систему новых клиентов и новые типы пиццы, после чего программа возвращает эти клиенты и векторы пиццы с этими данными.

Функция neworder () просит пользователя ввести идентификатор номера клиента и пицца, которая будет составлять заказ. Затем программа ищет эти идентификационные номера и, если есть совпадение, просит пользователя подтвердить, что эти идентификаторы представляют правильного клиента и пиццу.

Как только пользователь подтвердит, что заказ правильный, я бы хотел сделать sh возврат вектора заказов класса Order, чтобы включить компоненты вектора пиццы и вектора клиентов, которые соответствуют идентификаторам, которые дал пользователь ,

Например, если пользователь вводит идентификаторы 0 0 и подтверждает, что это правильный выбор, я хотел бы, чтобы программа отодвинула вектор заказов с обоими информацией, хранящейся в x. пиццы [0] (0, "пшеница", "аматрициана", "проволоне", "кальмар") и информация, хранящаяся в y.customers [0] {0, "Bjarne", "Stroustrup" }. (Обратите внимание, что идентификационные номера соответствуют позициям вектора.)

Каков наилучший способ сделать это? Спасибо как всегда за вашу помощь!

//Test to see how I can get a vector in one class to store elements from vectors from two other classes

using namespace std;
#include <iostream>
#include <vector>

class Pizza
{
public:
    string crust;
    string sauce;
    //Mmm... string cheese
    string cheese;
    string topping;
    int pizzaid;
    vector<Pizza> pizzas;
    void addtomenu();

    Pizza(int a, string b, string c, string d, string e)
        : pizzaid{a}, crust{b}, sauce{c}, cheese{d}, topping{e} {}
};

class Customer
{
public:
    string firstname;
    string lastname;
    int customerid;
    vector<Customer> customers;
    void addcustomer();
    Customer(int a, string b, string c)
        : customerid{a}, firstname{b}, lastname{c} {}
};

class Order
{
public:
    Pizza orderedpizza;
    Customer customerordering;
    int orderid;
    vector<Order> orders;
    void neworder();
    void data();
    Order(Pizza a, Customer b)
        : orderedpizza{a}, customerordering{b} {}
};

//I added in these placeholder objects so that I could run functions/push back vectors that belong to these functions' classes. I'm not sure whether there is a more sophisticated way to do this.
//I used negative integers just in case positive ones would interfere with actual pizza/customer IDs.
Pizza x{-1, " ", " ", " ", " "};
Customer y{-1, " ", " "};
Order z{x, y};

void Pizza::addtomenu()
{
    cout << "Please enter the crust, sauce, cheese, and topping that this pizza will have, all separated by spaces.\n";
    cin >> crust >> sauce >> cheese >> topping;
    pizzaid = pizzas.size();
    x.pizzas.push_back(Pizza{pizzaid, crust, sauce, cheese, topping});
    cout << "The pizza has been added.\n";
}

void Customer::addcustomer()
{
    cout << "Please enter the first and last name of the customer, separated by spaces.\n";
    cin >> firstname >> lastname;
    customerid = customers.size();
    y.customers.push_back(Customer{customerid, firstname, lastname});
    cout << "The customer has been added.\n";
}

void Order::neworder()
{
    int tempcustomerid;
    int temppizzaid;
    bool trueflag1 = 0;
    bool trueflag2 = 0;
    string entry;
    cout << "Please enter the customer's ID, followed by the ID of the pizza being ordered. Separate the two with spaces.\n";
    if (cin >> tempcustomerid >> temppizzaid)
    {
        for (int d = 0; d < y.customers.size(); d++)
        {
            if (tempcustomerid == y.customers[d].customerid)
            {
                trueflag1 = 1;
                tempcustomerid = d;
            }
        }

        if (trueflag1 == 0)
        {
            cin.clear();
            cin.ignore(1000, '\n');
            cout << "That ID does not match any customer in the system.\n";
            return;
        }

        for (int e = 0; e < x.pizzas.size(); e++)
        {
            if (temppizzaid == x.pizzas[e].pizzaid)
            {
                cin.clear();
                cin.ignore(1000, '\n');
                trueflag2 = 1;
                temppizzaid = e;
            }
        }

        if (trueflag2 == 0)
        {
            cout << "That ID does not match any pizza in the system.\n";
            return;
        }

        {
            cout << "The following customer: " << y.customers[tempcustomerid].customerid << " " << y.customers[tempcustomerid].firstname << " " << y.customers[tempcustomerid].lastname << " ";
            cout << "will be ordering the following pizza: " << x.pizzas[temppizzaid].pizzaid << " " << x.pizzas[temppizzaid].crust << " " << x.pizzas[temppizzaid].sauce << " " << x.pizzas[temppizzaid].cheese << " " << x.pizzas[temppizzaid].topping << ".\n";
            cout << "Is that correct? If yes, press 1; if no, press 0.\n";
            cin >> entry;
            if (entry == "1")
            {
                //Here, I would like to push back my orders vector to include the contents of y.customers[tempcustomerid] and y.pizzas[temppizaid]. What would be the best way to do this?

                cout << "The order has been placed.\n";
            }
            else
            {
                cout << "Order canceled.\n";
                return;
            }
        }
    }
    else
    {
        cin.clear();
        cin.ignore(10000, '\n');
        cout << "Please enter your input in integer form.\n";
    }
}

void Order::data()
{
    cout << "Pizzas entered into system so far:\n";
    for (int d = 0; d < x.pizzas.size(); d++)
    {
        cout << x.pizzas[d].pizzaid << " " << x.pizzas[d].crust << " " << x.pizzas[d].sauce << " " << x.pizzas[d].cheese << " " << x.pizzas[d].topping << "\n";
    }

    cout << "Customers entered into system so far:\n";
    for (int d = 0; d < y.customers.size(); d++)
    {
        cout << y.customers[d].customerid << " " << y.customers[d].firstname << " " << y.customers[d].lastname << "\n";
    }
}

int main()

{
    //These two push_back functions are added to create test items for debugging purposes.
    x.pizzas.push_back(Pizza{0, "wheat", "amatriciana", "provolone", "squid"});
    y.customers.push_back(Customer{0, "Bjarne", "Stroustrup"});

    string entry;
    while (true)
    {
        cout << "Welcome to the Pizza Orderer 5000. To enter a new customer, enter addcustomer. To enter a new pizza to the menu, enter addtomenu. To enter a new order, enter order. To list all data in the system, enter data. To quit, enter quit.\n";
        cin >> entry;
        if (entry == "addcustomer")
            y.addcustomer();
        else if (entry == "addtomenu")
            x.addtomenu();
        else if (entry == "order")
            z.neworder();
        else if (entry == "data")
            z.data();
        else if (entry == "quit")
            break;
        else
        {
            cin.clear();
            cin.ignore(10000, '\n');
            cout << "I'm sorry, that input was not recognized. Please try again.\n";
        }
    }
}

Answer 1

Комментарий

PaulMckenz ie вдохновил меня на решение этой проблемы, отодвинув вектор заказов с (копиями) customerid и pizzaid для каждого заказа, а не с самими классами Pizza и Customer. Затем информацию из вектора заказов можно использовать для воспроизведения информации из векторов пиццы и клиентов.

Вместо того, чтобы включать int pizzaid Pizzas и int customerid клиента в качестве членов класса Order, я сделал их копии. Я полагаю, что вместо этого можно было бы использовать оригинальные целые (и если да, пожалуйста, дайте мне знать).

Вот пересмотренный код с некоторыми дополнительными комментариями:

using namespace std;
#include <iostream>
#include <vector>

class Pizza
{
public:
    string crust;
    string sauce;
    //Mmm... string cheese
    string cheese;
    string topping;
    int pizzaid;
    vector<Pizza> pizzas;
    void addtomenu();

    Pizza(int a, string b, string c, string d, string e)
        : pizzaid{a}, crust{b}, sauce{c}, cheese{d}, topping{e} {}
};

class Customer
{
public:
    string firstname;
    string lastname;
    int customerid;
    vector<Customer> customers;
    void addcustomer();
    Customer(int a, string b, string c)
        : customerid{a}, firstname{b}, lastname{c} {}
};

class Order
{
public:
    int orderedpizzaid;
    int orderingcustomerid;
    int orderid;
    vector<Order> orders;
    void neworder();
    void data();
    Order (int a, int b, int c) 
    : orderid{a}, orderingcustomerid{b}, orderedpizzaid{c} {}
};

//I added in these placeholder objects so that I could run functions/push back vectors that belong to these functions' classes. I'm not sure whether there is a more sophisticated way to do this.
//I used negative integers just in case positive ones would interfere with actual pizza/customer IDs.
Pizza x{-1, " ", " ", " ", " "};
Customer y{-1, " ", " "};
Order z{-1, -1, -1};

void Pizza::addtomenu()
{
    cout << "Please enter the crust, sauce, cheese, and topping that this pizza will have, all separated by spaces.\n";
    cin >> crust >> sauce >> cheese >> topping;
    pizzaid = pizzas.size();
    x.pizzas.push_back(Pizza{pizzaid, crust, sauce, cheese, topping});
    cout << "The pizza has been added.\n";
}

void Customer::addcustomer()
{
    cout << "Please enter the first and last name of the customer, separated by spaces.\n";
    cin >> firstname >> lastname;
    customerid = customers.size();
    y.customers.push_back(Customer{customerid, firstname, lastname});
    cout << "The customer has been added.\n";
}

void Order::neworder()
{
    int orderid;
    int orderedpizzaid;
    int orderingcustomerid;
    bool trueflag1 = 0;
    bool trueflag2 = 0;
    string entry;
    cout << "Please enter the customer's ID, followed by the ID of the pizza being ordered. Separate the two with spaces.\n";
    if (cin >> orderingcustomerid >> orderedpizzaid)
    {
        for (int d = 0; d < y.customers.size(); d++)
        {
            if (orderingcustomerid == y.customers[d].customerid)
            {
                trueflag1 = 1;
                orderingcustomerid = d;
            }
        }

        if (trueflag1 == 0)
        {
            cin.clear();
            cin.ignore(1000, '\n');
            cout << "That ID does not match any customer in the system.\n";
            return;
        }

        for (int e = 0; e < x.pizzas.size(); e++)
        {
            if (orderedpizzaid == x.pizzas[e].pizzaid)
            {
                cin.clear();
                cin.ignore(1000, '\n');
                trueflag2 = 1;
                orderedpizzaid = e;
            }
        }

        if (trueflag2 == 0)
        {
            cout << "That ID does not match any pizza in the system.\n";
            return;
        }

        {
            cout << "The following customer: " << y.customers[orderingcustomerid].customerid << " " << y.customers[orderingcustomerid].firstname << " " << y.customers[orderingcustomerid].lastname << " ";
            cout << "will be ordering the following pizza: " << x.pizzas[orderedpizzaid].pizzaid << " " << x.pizzas[orderedpizzaid].crust << " " << x.pizzas[orderedpizzaid].sauce << " " << x.pizzas[orderedpizzaid].cheese << " " << x.pizzas[orderedpizzaid].topping << ".\n";
            cout << "Is that correct? If yes, press 1; if no, press 0.\n";
            cin >> entry;
            if (entry == "1")
            {orderid = orders.size();
            //The orders ID is pushed back with only the order ID and (copies of)
//the pizza and customer IDs. However, this information will be sufficient to 
//reproduce all of the customer and pizza information that corresponds to the 
//customer and pizza IDs, as shown in the data function. 
               z.orders.push_back(Order{orderid, orderingcustomerid, orderedpizzaid});
                cout << "The order has been placed.\n";
            }
            else
            {
                cout << "Order canceled.\n";
                return;
            }
        }
    }
    else
    {
        cin.clear();
        cin.ignore(10000, '\n');
        cout << "Please enter your input in integer form.\n";
    }
}

void Order::data()
{
    cout << "Pizzas entered into system so far:\n";
    for (int d = 0; d < x.pizzas.size(); d++)
    {
        cout << x.pizzas[d].pizzaid << " " << x.pizzas[d].crust << " " << x.pizzas[d].sauce << " " << x.pizzas[d].cheese << " " << x.pizzas[d].topping << "\n";
    }

    cout << "Customers entered into system so far:\n";
    for (int d = 0; d < y.customers.size(); d++)
    {
        cout << y.customers[d].customerid << " " << y.customers[d].firstname << " " << y.customers[d].lastname << "\n";
    }

cout << "Orders entered into system so far:\n";
for (int d = 0; d < z.orders.size(); d++)
    {
        //Each order is given an order ID that equals that order's position in the 
//orders vector. The orders vector stores both each order's ID and copies of the IDs
//of the pizza and customer that were included in that order.
        //Therefore, for each order in the orders vector, the following code: (1) prints
// the corresponding order id; (2) prints information from the customers vector for the 
//customer whose customerid matches the orders vector's orderingcustomerid; and (3) prints
// information from the pizzas vector for the pizza whose pizzaid matches the orders 
//vector's orderingpizzaid.
        cout << "Order ID: " << z.orders[d].orderid; 
        cout << " Customer information: " <<  y.customers[z.orders[d].orderingcustomerid].customerid << " " << y.customers[z.orders[d].orderingcustomerid].firstname << " " << y.customers[z.orders[d].orderingcustomerid].lastname;
        cout << " Pizza information: " << x.pizzas[z.orders[d].orderedpizzaid].pizzaid << " " << x.pizzas[z.orders[d].orderedpizzaid].crust << " " << x.pizzas[z.orders[d].orderedpizzaid].sauce << " " << x.pizzas[z.orders[d].orderedpizzaid].cheese << " " << x.pizzas[z.orders[d].orderedpizzaid].topping << "\n";
    }

}

int main()

{
    //These two push_back functions are added to create test items for debugging purposes.
    x.pizzas.push_back(Pizza{0, "wheat", "amatriciana", "provolone", "squid"});
    y.customers.push_back(Customer{0, "Bjarne", "Stroustrup"});

    string entry;
    while (true)
    {
        cout << "Welcome to the Pizza Orderer 5000. To enter a new customer, enter addcustomer. To enter a new pizza to the menu, enter addtomenu. To enter a new order, enter order. To list all data in the system, enter data. To quit, enter quit.\n";
        cin >> entry;
        if (entry == "addcustomer")
            y.addcustomer();
        else if (entry == "addtomenu")
            x.addtomenu();
        else if (entry == "order")
            z.neworder();
        else if (entry == "data")
            z.data();
        else if (entry == "quit")
            break;
        else
        {
            cin.clear();
            cin.ignore(10000, '\n');
            cout << "I'm sorry, that input was not recognized. Please try again.\n";
        }
    }
}