ex14_15.cpp

#include "ex14_15.h"

std::istream& operator>>(std::istream& in, Book& book)
{
    in >> book.no_ >> book.name_ >> book.author_ >> book.pubdate_ >>
        book.number_;
    if (!in) book = Book();
    return in;
}

std::ostream& operator<<(std::ostream& out, const Book& book)
{
    out << book.no_ << " " << book.name_ << " " << book.author_ << " "
        << book.pubdate_ << " " << book.number_ << std::endl;
    return out;
}

bool operator==(const Book& lhs, const Book& rhs)
{
    return lhs.no_ == rhs.no_;
}

bool operator!=(const Book& lhs, const Book& rhs)
{
    return !(lhs == rhs);
}

bool operator<(const Book& lhs, const Book& rhs)
{
    return lhs.no_ < rhs.no_;
}

bool operator>(const Book& lhs, const Book& rhs)
{
    return rhs < lhs;
}

Book& Book::operator+=(const Book& rhs)
{
    if (rhs == *this) this->number_ += rhs.number_;

    return *this;
}

Book operator+(const Book& lhs, const Book& rhs)
{
    Book book = lhs;
    book += rhs;
    return book;
}