Affiliation: | 1. School of Mathematical Sciences, Luoyang Normal University, Luoyang 471022, China;2. State Key Laboratory of Information Security, Institute of Information Engineering, Chinese Academy of Sciences, Beijing 100093, China;3. State Key Laboratory of Cryptology, P.O. Box 5159, Beijing 100878, China;4. Beijing Center for Mathematics and Information Interdisciplinary Sciences, Beijing 100048, China |