| 摘要 |
PROBLEM TO BE SOLVED: To grasp an actual object about a book to be borrowed.SOLUTION: This method includes processing for specifying an identifier of a first book selected by a user (A), extracting an identifier of a second book associated with the user's identifier from a first data storage part for storing the identifier of the book and an identifier of a borrower user by associating the identifier of the book with the identifier of the borrower user (B), extracting at least one of a size and a quantity associated with the identifier of the second book from a second data storage part for storing at least one of a size and quantity of a book and an identifier of the book by associating at least one of the size and the quantity of the book with the identifier of the book (C), and generating and outputting data representing difference between at least one of the size and the quantity associated with the identifier of the first book in the second data storage part and at least one of the size and the quantity of the second book (D). |
