The first Chinese medical text in China is?

The Yellow Emperor's Classic of Internal Medicine is divided into two parts, Ling Shu and Su Wen, which is the work of the ancient medical doctors who entrusted the name of Emperor Xuanyuan Huangdi to the joint creation of medical doctors and medical theorists, and it is generally believed to have been written in the Spring and Autumn and the Warring States periods. While elaborating on the mechanism and pathology of diseases in the form of dialogues and questions and answers among Huangdi, Qibo and Leigong, the book advocates not treating the disease, but treating the disease before it occurs, and at the same time, advocates nourishment, regimen, longevity and prolongation of life. It is one of the four classic works of traditional Chinese medicine (Huangdi Neijing, Nanking, Typhoid Miscellaneous Diseases, Shennong Ben Cao Jing), and is the earliest surviving medical text in the medical treasury of China. It is a medical masterpiece that studies human physiology, pathology, diagnostics, treatment principles and pharmacology. In theory, the establishment of Chinese medicine on the "yin and yang five elements doctrine", "pulse doctrine" "Tibetan elephant doctrine" and so on.