"People who analyze algorithms have double happiness..." Donald E.Knuth (1938~) Hengfeng Wei (hfweixinju.edu.cn) 2-3 Counting March12,20203/34“People who analyze algorithms have double happiness . . .” Donald E. Knuth (1938 ∼) Hengfeng Wei (hfwei@nju.edu.cn) 2-3 Counting March 12, 2020 3 / 34