How did heavenly stems and earthly branches calculate it? Who can tell this popular story?

Heavenly stems and earthly branches is used in ancient calendars. Tianganyou 10, a, b, c, d, e, g, n, n, Dizhi 12 is 12 zodiac. Divide heavenly stems and earthly branches into Yin and Yang. There are five yin and five yang in the sky, and six yin and six yang in the ground. Then heavenly stems and earthly branches arranged and combined, Yin to Yin, Yang to Yang. Starting from Jiazi, Jiazi, Ugly B, Bingyin and Ding Mao ... * * * 60 cycles end, commonly known as Jiazi, 60 years! As for the year of the Sino-Japanese War of 1894, it is 1894, which means that this year is 20 12, and the other way around. Fortune tellers have a unique method in their hands. They can count by pinching their fingers. Ordinary people just find a pen and a piece of paper and do it slowly by themselves!