说明：  建立顺序表，实现取元素、判断表是否为空、求表长、打印、查找、求前驱、求后继、插入、删除等操作。编写就地逆置顺序表的算法，即利用原表的存储空间将线性表(a1, a2, … , an) 逆置为(an , … ,a2 , a1 )
(Established order of the table to achieve taking elements to determine whether the table is empty, seeking long table, print, search, find precursor, seeking successor, insert, and delete operations. Prepared in situ reverse order of the table set algorithm, using the original table storage space linear form (a1, a2, ..., an) is set to the inverse (an, ..., a2, a1))