实现一个一元多项式简单的加法计算器。 一元多项式简单的加法计算器的基本功能为：

（1）输入并建立多项式；

（2）输出多项式；

（3）两个多项式相加，并建立输出多项式。

用带头结点的有序链表

-One of the polynomial realization of a simple adder calculator. One simple addition of the polynomial calculator for basic functions: (1) input and the establishment of polynomials　(2) the output polynomial　(3) the sum of two polynomials, and the establishment of the output polynomial. Used to take the lead in node list in an orderly