Andrew McCarthy, author of "St. Elmo's Fire," has shared his six favorite books, which he switches between physical and nonfiction. His new book, "Who Needs Friends: An Unscientific Examination of Male Friendship Across America," is out now. McCarthy prefers to read novels and listen to nonfiction, preferring to process information through a physical copy. His recommendations include a modern retelling of Dickens' David Copperfield and a hard-boiled detective novel by Edward Hammett.