Introduction - If you have any usage issues, please Google them yourself
The date of the establishment of a category to calculate the relationship between the date of the special judge ① to judge whether it is a leap year ② According to judge the outcome of a leap year to determine the specific deadline for the month of February the number of days ③, respectively, of large month (31 days) and Xiaoyue (30 days ) different at the end of the month whether or not to judge ④ judge on whether or not New Year.