файл DeliveryInformation.h

#pragma once
#include <iostream>
#include "ProductInformation.h"
using namespace std;

class DeliveryInformation: public ProductInformation
{
private:
	float charges_;
	string customer_;
	string supplyer_;
public:
	DeliveryInformation() :ProductInformation(), charges_(0.0), customer_(""), supplyer_(""){};
	//~DeliveryInformation();
	float getCharges() const { return charges_; };
	string getCustomer()const { return customer_; };
	string getSupplyer() const { return supplyer_;};
	float getAmountOfProduct() const { return amountOfProduct_; };
	float getProductPrice() const { return productPrice_;};
	string getProductName() const {	return productName_; };

	void setCharges(float charges) { charges_ = charges;};
	void setCustomer(string customer) { customer_ = customer; };
	void setSupplyer(string supplyer) { supplyer_ = supplyer; };
    void setAmountOfProduct(float amountOfProduct){ amountOfProduct_ = amountOfProduct;};
	void setProductPrice(float productPrice) { productPrice_ = productPrice;};
	void setProductName(string productName) {productName_ = productName;};
	void createNewProduct();
	void deleteOneProduct();
	friend istream& operator >> (istream& input, DeliveryInformation& obj) {
		input >> obj.productName_ >> obj.amountOfProduct_ >> obj.productPrice_ >>
			obj.charges_ >> obj.supplyer_ >> obj.customer_;
		return input;
	};
	friend ostream& operator << (ostream& output, DeliveryInformation& obj) {
		output << obj.productName_ << "\n" << obj.amountOfProduct_ << "\n" << obj.productPrice_
			<< "\n" << obj.charges_ << "\n" << obj.supplyer_ << "\n" << obj.customer_ << "\n";
		return output;
	};
};

файл ProductInformation.h

#pragma once
#include <iostream>
using namespace std;

class ProductInformation
{
protected:
	float amountOfProduct_;
	string productName_;
	float productPrice_;
public:
	ProductInformation() : amountOfProduct_(0.0),
		productName_(""), productPrice_(0.0) {};
	//~ProductInformation();
	virtual float getAmountOfProduct() const = 0;
	virtual float getProductPrice() const = 0;
	virtual string getProductName() const = 0;
	virtual void setAmountOfProduct(float) = 0;
	virtual void setProductPrice(float) = 0;
	virtual void setProductName(string) = 0;
};