C++ - I have created a project in C++ and have commented some lines of code. Are the comments an accurate reflection of the code?

#include <iostream>

using namespace std;

class Book {
private:
    string title;
    string author;
public:
    Book() { cout << "Book created." << endl; };
    Book(const Book& other) : title(other.title) { cout << "Book created by copying.\n" << endl; };
    void setTitle(string title) { this->title = title; };
    void display() const { cout << "Book title: " << title << endl; }
};


int main()
{
    Book book1;
    book1.setTitle("Book1.");

    // Calling the copy constructor using the equal sign
    Book book2 = book1;
    cout << "Book 1 called through copy constructor: " << endl;

    // Object (book2) of the class Book being passed to a function called "display()"
    book2.display();

    // Set title for book 2
    book2.setTitle("Book2.");
    cout << endl;

    cout << "Book 1" << endl;
    book1.display();
    cout << endl;

    cout << "Calling Book 2 via copy constructor through Book 4:" << endl;
    Book book4 = book2;
    book2.display();
    cout << endl;

    // Another way to invoke the copy constructor directly
    cout << "Book 1: Direct invocation" << endl;
    Book book3(book1);

    cout << "Calling the copy constructor through the object, book 3: " << endl;
    book3.display();


    return 0;
}