How does the Xiaomi Robot Vacuum X20 Max sweep the whole house?

When there is no saved map, selecting whole-house cleanup mode will cause the Xiaomi Robot Vacuum X20 Max to clean in a square area of 4.5m x 4.5m. Then it will use a bow-shaped cleaning method until all areas are covered.
After saving the map, the robot vacuum will clean according to the room, starting with the edge cleaning and then the bow-shaped cleaning, completing the cleaning of the room in sequence. To avoid secondary pollution caused by the robot vacuum passing through a cleaned room, the vacuuming and mopping modes have a different cleaning sequence from the vacuuming mode.