根据线性表的抽象数据类型的定义，选择任一种链式结构实现线性表，并完成线性表的基本功能。编写测试main()函数测试线性表的正确性。-According to the linear form of the definition of abstract data types, select one of the chain structure of the linear form, and complete the basic functions of the linear form. Prepar