How to calculate the time of entering voltage?

Accommodation time: the third Geng Day after long summer; Sailing time: the first Geng Day after beginning of autumn.

The algorithm of crouching time is as follows: crouching means entering the dog days.

That is, from summer to the third "night" in the future, the first onset is 10 day, the second onset is 10 day and 20 days, and the last onset is 10 day.

The dog days are the hottest thirty or forty days in a year in the Central Plains. The dog days are calculated according to the lunar calendar, between the middle and late July and the early August of the solar calendar.

The crouching time is not fixed every year, and the length of crouching time is also different.