Write a C++ class that is derived from the Progression class to produce a progression where each value is the absolute value of the difference between the previous two values. You should include a default constructor that starts with 2 and 200 as the first two values and a parametric constructor that starts with a specified pair of numbers as the first two values.

Here is the Progression class to derive from

class Progression {

public:

Progression(long f = 0) // constructor

: first(f), cur(f) { }

virtual Progression() { }; // destructor

void printProgression(int n); // print the first n values

protected:

virtual long firstValue(); // reset

virtual long nextValue(); // advance

protected: long first; // first

value long cur; // current value

};