Hints on Assignment 2.
----------------------

1. In testpoly.cc, to test the constructor with no arguments, you
would type:

  Polynomial A;       // create a polynomial

  A.PrintPoly();      // print out the polynomial, should print 0

Note that you cannot say:

  cout << A << endl;

Since "<<" only knows how to print out built-in types such as int and
double. In order to use the cout statement above, you would have to
define an "<<" operator and tell it how to print out a polynomial.
That is not part of this assignment. Instead, we will print out
using the PrintPoly function.

To be safe, when you create the 0 polynomial above, it should be
a linked list with one node that has 0 as the term and 0 as the
coefficient.

2. To create a Polynomial 8.2 x^7 + 3.1x^4

there is no constructor to do this. You will have to first construct
the zero polynomial, and then use SetCoefficient to add in the proper
terms.

  Polynomial C;               
  C.SetCoefficient(7, 8.2);   
  C.SetCoefficient(4, 3.1);

  result is a linked list with 2 or 3 nodes depending on whether or not
  you want to delete the zero node.

  C.PrintPoly() should print out 8.2 * x^7 + 3.1 * x^4

  Note: 0 should not be printed out if there are other terms.   

You should first create your constructors and PrintPoly() and make
sure this work before trying any of the other functions.