I used to suffer from insomnia. I couldn't sleep over and over again. Sometimes thousands of sheep do not feel sleepy.

I remember one time, I really couldn't sleep, so I took out advanced mathematics that I didn't read many years ago.

After watching it for less than ten minutes, the upper and lower eyelids began to fight. Before reading a page, I was already sleepy and took a nap.

From then on, as long as I can't sleep, I will watch Gao Shu and sleep until dawn.