Introduction to Cao Chong's "Three Kingdoms": "Three Kingdoms" records: Cao Chong was five or six years old, as wise as an adult. At that time, Sun Quan once sent a giant elephant. Taizu wanted to know its weight, so he visited a group of people, but they couldn't figure it out. Chong said: "Put it on a large elephant ship, carve the mark of the water, weigh the object to carry it, and then you can know it." Taizu was very happy, and he implemented it.