struct & array .net console

struct & array

struct Books 
{
   public string title;
   public string author;
   public string subject;
   public int book_id;
};

Books[] arr = new Books[4];
            for(int i = 0; i < 4; i++)
            {
            Console.WriteLine("Please enter title");
            arr[i].title= Console.ReadLine();
            Console.WriteLine("Please enter author");
            arr[i].author = Console.ReadLine();
            Console.WriteLine("Please enter subject");
            arr[i].subject = Console.ReadLine();
            Console.WriteLine("Please enter book id");
            arr[i].book_id = int.Parse(Console.ReadLine());
            Console.Clear();
            }