Design and implement a class that is a class for polynomials. The polynomial

a_nxⁿ + a_n-1x^n-1 + ... + a₀

will be implemented as a linked list. Each node will contain an int value for the power of x and an int value for the corresponding coefficient. The class operations should include addition, subtraction, multiplication, and evaluation of a polynomial. Overload the operators +, -, and * for addition, subtraction, and multiplication. Evaluation of a polynomial is implemented as a member function with one argument of type int . The evaluation member function returns the value obtained by plugging in its argument for x and performing the indicated operations.

Include four constructors: a default constructor, a copy constructor, a constructor with a single argument of type int that produces the polynomial that has only one constant term that is equal to the constructor argument, and a constructor with two arguments of type int that produces the one-term polynomial whose coefficient and exponent are given by the two arguments. (In the previous notation, the polynomial produced by the one-argument constructor is of the simple form consisting of only a₀. The polynomial produced by the two-argument constructor is of the slightly more complicated form a_nxⁿ.) Include a suitable destructor. Include member functions to input and output polynomials.

When the user inputs a polynomial, the user types in the following:

a_nx^n + a_n-1x^n-1 + ... + a₀

However, if a coefficient a_i is 0, the user may omit the term a_ix^i. For example, the polynomial

3x⁴ + 7x² + 5

can be input as

3x^4 + 7x^2 + 5

It could also be input as

3x^4 + 0x^3 + 7x^2 + 0x^1 + 5

If a coefficient is negative, a minus sign is used in place of a plus sign, as in the following examples:

3x^5 - 7x^3 + 2x^1 – 8

-7x^4 + 5x^2 + 9

A minus sign at the front of the polynomial, as in the second of the previous two examples, applies only to the first coefficient; it does not negate the entire polynomial. Polynomials are output in the same format. In the case of output, the terms with 0 coefficients are not output. To simplify input, you can assume that polynomials are always entered one per line and that there will always be a constant term a 0. If there is no constant term, the user enters 0 for the constant term, as in the following:

12x^8 + 3x^2 + 0