#include <iostream> #include "Sales_item.h" int main() { Sales_item total; if (std::cin >> total) { Sales_item trans; while (std::cin >> trans) { if (total.isbn() == trans.isbn()) total += trans; else { std::cout << total << std::endl; total = trans; } } std::cout << total << std::endl; } else { std::cerr << "No data!" << std::endl; return -1; } return 0; }