Sample Program with Classes

#include <iostream>
#include <cstring>
#include <cinttypes>

class Book {
private:
    std::string name, author, publisher;
    uint32_t publishYear, pageCount;

public:
    Book(const std::string name, const std::string author, const std::string publisher, uint32_t publishYear,
         uint32_t pageCount) {
        this->name = name;
        this->author = author;
        this->publisher = publisher;
        this->publishYear = publishYear;
        this->pageCount = pageCount;
    }

    void printBook(bool isList = false) {
        if(isList) std::cout << " - ";
        std::cout << "Name: " << this->name
                  << " | Author: " << this->author
                  << " | Publisher: " << this->publisher
                  << " | Publish Year: " << this->publishYear
                  << " | Page Count: " << this->pageCount
                  << std::endl;
    }

    uint32_t getYear() { return this->publishYear; }
};

class Library {
private:
    std::string name;
    uint32_t bookCount;
    Book** books;

public:
    Library(const std::string name) {
        this->name = name;
        this->bookCount = 0;
        this->books = new Book*[bookCount];
    }

    void insertBooks() {
        bool insertMoreBooks = true;
        char userDecision;
        while(insertMoreBooks) {
            std::cout << "Do you want to insert book? (Y/N) ";
            std::cin >> userDecision;
            if(userDecision == 'N' || userDecision == 'n') {
                insertMoreBooks = false;
                break;
            }

            std::string name, author, publisher;
            uint32_t publishYear, pagesCount;

            std::cin.ignore();
            std::cout << "Name: ";
            std::getline(std::cin, name);
            std::cout << "Author: ";
            std::getline(std::cin, author);
            std::cout << "Publisher: ";
            std::getline(std::cin, publisher);
            std::cout << "Publish Year: ";
            std::cin >> publishYear;
            std::cout << "Page Count: ";
            std::cin >> pagesCount;

            Book* insertedBook = this->addBook(name, author, publisher, publishYear, pagesCount);
            std::cout << "Inserted book: ";
            insertedBook->printBook();
        }
    }

    Book* addBook(const std::string name, const std::string author, const std::string publisher, uint32_t publishYear,
                 uint32_t pageCount) {
        this->bookCount++;

        Book** oldBooks = this->books;
        this->books = new Book*[bookCount];
        for(int i = 0; i < bookCount - 1; i++) {
            this->books[i] = oldBooks[i];
        }

        this->books[bookCount-1] = new Book(name, author, publisher, publishYear, pageCount);

        return this->books[bookCount-1];
    }

    void printBooks() {
        for(int i = 0; i < bookCount; i++) {
            this->books[i]->printBook(true);
        }
    }

    Book* getOldestBook() {
        Book* oldestBook = this->books[0];
        for(int i = 0; i < bookCount; i++) {
            if(this->books[i]->getYear() < oldestBook->getYear()) oldestBook = this->books[i];
        }
        return oldestBook;
    }

    uint32_t getAvgBookYear() {
        uint32_t yearSum = 0;
        for(int i = 0; i < bookCount; i++) {
            yearSum += this->books[i]->getYear();
        }
        return static_cast<uint32_t>(yearSum / bookCount);
    }
};

int main() {
    // Create library
    Library myLib("My Library");
    std::cout << "Librarian, welcome to your new workplace! Be prepared for everything..."
              << std::endl
              << "--------------------------------------------------"
              << std::endl;

    // Add books to library
    //myLib.addBook("Don Quixote", "Miguel de Cervantes", "Ancient Stuff", 1615, 928);
    //myLib.addBook("1984", "George Orwell", "Harvill Secker", 1949, 336);
    std::cout << "Well, I guess we should start somewhere..."
              << std::endl;
    myLib.insertBooks();
    std::cout << "--------------------------------------------------"
              << std::endl;

    // Print all books
    std::cout << std::endl
              << "Phew... After all these keystrokes I guess you want to see your work... Look below :D "
              << std::endl;
    myLib.printBooks();
    std::cout << "--------------------------------------------------"
              << std::endl;

    // Find oldest book
    std::cout << std::endl
              << "But... you must keep an eye on the oldest one because some people would want to steal it."
              << std::endl
              << "The oldest book is: "
              << std::endl;
    Book* oldestBook = myLib.getOldestBook();
    oldestBook->printBook();
    std::cout << "--------------------------------------------------"
              << std::endl;

    // Get avg publish year
    std::cout << std::endl
              << "The legend says that the last Librarian was born at the average book year in the library when the new one step into the library for the first time..."
              << std::endl
              << "The last librarian's birth year was "
              << myLib.getAvgBookYear()
              << std::endl;
    std::cout << "--------------------------------------------------"
              << std::endl;

    return 0;
}