How to calculate the leap year of primary school mathematics?

In the Gregorian calendar (Gregorian calendar), a year with leap days is called leap year, which is generally 365 days and 366 days. Because the earth's cycle around the sun is 365 days, 5 hours, 48 minutes and 46 seconds (365,438+09 days), which is the tropic year, the Gregorian calendar sets a year as 365 days. The remaining time is about one day in four years, plus February, so the normal year is 365 days, February is 28 days, leap year is 366 days, and February is 29 days. So every 400 years, there are 97 leap years, with one day added at the end of February and 366 days in leap years. Calculation method of leap year: the number of years in the calendar year can be divisible by four, which is a leap year; Divided by 100 but not divided by 400 is an average year; Leap years can be divisible by 100 or 400. For example, 2000 is a leap year, and 1900 is not. The following is an example of calculating leap year in Gregorian calendar: s = InputBox ("Please enter year:") n = val (s) ifnmod 400 = 0 or (nmod 4 = 0 and nmod100.