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    <p>The concept is you have a library with some books. So an OOP approach may be create a class Library with some method. Like:</p> <pre><code>function Library() { var books = []; this.addBook = function(bookName,rate) { books.push({name:bookName, rating:rate}); } this.printBooks = function() { for(var i = 0; i &lt; books.length; i++) { document.writeln(books[i].name +": " + books[i].rating); } } } </code></pre> <p>code:</p> <pre><code>var myLibrary = new Library(); myLibrary.addBook('Silmarillion',9); myLibrary.addBook('Horus Rising',8); myLibrary.addBook('Lord of the Rings',7); myLibrary.printBooks(); </code></pre> <p><strong>However, it can be improved.</strong> You can create a class <code>Book</code>:</p> <pre><code>function Book(name,options) { this.name = name; this.rating = options.rating; } </code></pre> <p>and class Library becomes:</p> <pre><code>function Library() { var books = []; this.addBook = function(book) { books.push(book); } this.printBooks = function() { for(var i = 0; i &lt; books.length; i++) { document.writeln(books[i].name +": " + books[i].rating); } } // EDIT: ADDED for new features required this.countBook = function() { return books.length; } this.calculateRatingAverage = function() { var sum = 0; for(var i = 0; i &lt; books.length; i++) { sum += books[i].rating; } return sum/books.length; } } </code></pre> <p>and its use becomes:</p> <pre><code>var myLibrary = new Library(); myLibrary.addBook(new Book('Silmarillion',{rating:9})); myLibrary.addBook(new Book('Horus Rising',{rating:8})); myLibrary.addBook(new Book('Lord of the Rings',{rating:7})); myLibrary.printBooks(); document.writeln("&lt;br&gt;Number of books read: " + myLibrary.countBook() + "&lt;br&gt;The average rating of the books are: " + myLibrary.calculateRatingAverage()); </code></pre> <p>So you have a solid structure that you can optimize and work on it.</p>
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    1. USLuca Rainone
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    1. COThis seems to do the trick.. I'd just like you to help me add a function that writes out the average rating of the books as well to make it all complete :)
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    2. COCreating the `Book` object as a parameter seems a little unintuitive to me. It would be much neater if the object was created inside the `addBook` method and only the data is passed as the parameter.
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    3. CO@amustill the object Book has sense if the problem becomes more complex. So you have an object that you can complicate as you want. It's the reason why it's a complement of the answer
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