#include <iostream>
#include <string>
#include <vector>

using namespace std;

class Book {
private:
    string name;
    vector<string> authors;
    string dateTaken;
public:
    Book(string name, string author, string date) {
        this->name = name;
        this->authors.push_back(author);
        this->dateTaken = date;
    }

    Book(string name, vector<string> authors, string date) {
        this->name = name;
        this->dateTaken = date;

        this->authors.insert(this->authors.end(), authors.begin(), authors.end());
    }

    string getName() const { return this->name; }
    string getDateTaken() const { return this->dateTaken; }
    vector<string> getAuthors() const { return this->authors; }

    friend ostream& operator<<(ostream& os, const Book& book);
};

ostream &operator<<(ostream &os, const Book& book) {
    os << "Book name: " << book.getName() << "\n";

    return os;
}

class Library {
private:
    int bookCount;
    vector<Book> books;
public:
    void addBook(const Book& book) {
        bookCount++;
        this->books.push_back(book);
    }

    void addBooks(vector<Book> booksVector) {
        bookCount += booksVector.size();
        this->books.insert(this->books.end(), booksVector.begin(), booksVector.end());
    }

    vector<Book> filterByDateTaken(const string& date) {
        vector<Book> takenBooks;
        for (auto & book : this->books) {
            if (book.getDateTaken() == date) {
                takenBooks.push_back(book);
            }
        }

        return takenBooks;
    }
};

int main() {

    return 0;
}