The bill 12. 15 was generated, and the transactions during the period of 16- 12. 15 were recorded. The final repayment date was 65438, and the date after 12. 15.

Generate a bill 1. 15, and record the transactions during12.16-1. 15, and the final repayment date is after1.15.

And so on.

Obviously, 12. 15 has the shortest interest-free period of 25 days (12. 15, 1.9), and the first day after the billing date12./kloc-0. It should be noted that credit card consumption has an interest-free period, and cash withdrawal has no interest-free period.