How many bus companies are there in Nanjing?

Nanjing Public Transport Corporation Nanjing Zhongbei Bus Company (including Zhongbei Pukou and Zhongbei Liuhe) Nanjing Accor Bus Company Nanjing Xincheng Bus Company Nanjing Xinningpu Bus Company (a subsidiary of Nanjing Public Transport Corporation) Nanjing Tongsheng Passenger Transport Company Nanjing Jinling Transportation Company (operating Liu Han, Zhonghua Gate to Liuhe Line)