（1）输入并建立多项式。
（2）输出多项式，输出形式为整数序列：n，c1，e1，c1，c2，e2，…，cn，en，其中n是多项式的项数，ci，ei，分别是第i项的系数和指数，序列按指数降序排序。
（3）实现多项式a和b相加，建立多项式a+b。
（4）实现多项式a和b相减，建立多项式a-b。
（5）计算多项式在x处的值。((1) input and establish polynomial.
(2) output polynomial, the output form is integer sequence: n, C1, E1, C1, C2, e2,... Cn, en, N, which is a polynomial number of entries, CI, EI, respectively, the coefficient and index of item I, sequence index sorted in descending order.
(3) polynomial A and B are added, and polynomial a+b is established.
(4) polynomial A and B subtraction, the establishment of polynomial a-b.
(5) calculate the value of the polynomial at X.)