Li Bai, a great poet in the Tang Dynasty, is not only a good poet, but also a good drinker. Du Fu said that he was "one hundred poems of Li Bai's fighting for wine". Legend has it that Li Bai once had

Li Bai, a great poet in the Tang Dynasty, is not only a good poet, but also a good drinker. Du Fu said that he was "one hundred poems of Li Bai's fighting for wine". Legend has it that Li Bai once had a math class while drinking. "When you meet a shop, double it and have a drink every flower." Three encounters with shop flowers, lamps and bottles of wine. "This means walking down the street with a hip flask. Meet the hotel, double the wine in the hip flask, meet the flowers and drink a barrel of wine. I met the hotel and flowers three times and got drunk.

Reverse calculation.

1) Before I met the flowers for the third time, there were 1 barrel in the pot. Before meeting the hotel for the third time, the wine in the pot was 1/2=0.5 dou;

2) Before the second encounter with flowers, there were (1+0.5) barrels in the basin. Before I saw the hotel for the second time, the wine in the pot was (1+0.5)/2=0.75.

3) Before I met the flowers for the first time, there were (1+0.75) barrels in the basin. Before I first met the hotel, the wine in the pot was (1+0.75)/2=0.875.

0.875 barrel is the capacity in the original hip flask.