1. School of Mathematics and Statistics, Guangxi Normal University, Guilin, China
2. School of Mathematics and Statistics and the Center for Applied Mathematics of Guangxi, Guangxi Normal University, Guilin, China
3. Department of Computer Science, Computing and Information Technology, King Abdulaziz University, Jeddah, Saudi Arabia
4. Institute of Architecture Engineering, Guangxi City Vocational University, Chongzuo, China