1923: Sorting Books

Define a book class which consists of three non-static data fields ,including "bookName"(the name of a book), "bookPrice"(the price of a book),and "bookNums"(the number of a book)

There are many cases , and for each case ,the first line is to input a integer n  to denote the number of books,and a character 'A' or 'D' to denote a sorting in ascending order and descending order of age.

 then input n books, including a book's name,a book's price, and the number of book.

4 A
Flipped 79.8 20
Pride 49.8 2
living 35.0 2
happiness 69.0 1
4 D
Flipped 79.8 20
Pride 49.8 2
living 35.0 2
happiness 69.0 1

books in ascending price are：
living 35.0￥ 2
Pride 49.8￥ 2
happiness 69.0￥ 1
Flipped 79.8￥ 20
books in descending price are：
Flipped 79.8￥ 20
happiness 69.0￥ 1
Pride 49.8￥ 2
living 35.0￥ 2