完成对循环队列结构的定义，以及对循环队列的各种基本运算的实现（每种基本运算用一个函数来实现）。 基本运算包括：初始化Init_sqqueue运算、判队空Empty_sqqueue运算、入队En_sqqueue运算、出队De_sqqueue运算、取队头元素Gethead_sqqueue运算。 -Completion of the circular queue structure is defined, and the circular queue implementation of various basic operations (each basic operations to implement a function). Basic operations include: initialization Init_sqqueue operations, sub-team empty Empty_sqqueue operations into the team En_sqqueue operations, the team De_sqqueue operations team to take the first element Gethead_sqqueue operations.