public class Exercise11 {
    
    public static void main(String[] args) {
        // System.out.println("-------------------------------");
        
        Book book1 = new Book("XXX", 3500);
        book1.print();
        
        // System.out.println("-------------------------------");
        
        Book book2 = new Book("YYY", 2000, "B5");
        book2.print();
        book2.price = 2500;
        book2.print();
        book2.setPrice(2400);
        book2.print();
        
        // System.out.println("-------------------------------");
        
        Book book3 = book1;
        book1.print();
        book1 = new Book("ZZZ", 3500);
        book1.setPrice(3000);
        book1.print();
        book3.print();
        
        // System.out.println("-------------------------------");
        
        book3 = book2;
        book3.setPrice(2300);
        book3.print();
        book2.setPrice(2200);
        book3.print();
        
        // System.out.println("-------------------------------");
        
        book3 = book1;
        book3.print();
        
        // System.out.println("-------------------------------");
    }
}