ex2_42_2.cpp

#include <iostream>

#include "ex2_42_sales_data.h"

int main()
{
    Sales_data book1, book2;
    double price1, price2;
    std::cin >> book1.bookNo >> book1.units_sold >> price1;
    std::cin >> book2.bookNo >> book2.units_sold >> price2;
    book1.CalcRevenue(price1);
    book2.CalcRevenue(price2);

    if (book1.bookNo == book2.bookNo) {
        book1.AddData(book2);
        book1.Print();

        return 0;
    }
    else {
        std::cerr << "Data must refer to same ISBN" << std::endl;
        return -1; // indicate failure
    }
}