Who is better, Zhang Sen or Liu Bingsen?

Who is better than Zhang Sen and Liu Bingsen? Zhang Sheng is a martial artist with good kung fu. His kung fu is very diligent, powerful, muscular and smart. He has practiced martial arts for more than ten years, so his kung fu foundation is much better than that of Zhang Sen. Zhang Sen is thin, not so strong, and his kung fu is not very strong, so Liu Bingsen is much worse than Zhang Sen.