Multiple inheritance C++ program to show the sum of an A.P. series

Write a c++ program to find out the sum of an A.P. series by using the multiple inheritances in object-oriented programming.

class diagram of sum of an A.P. series Multiple Inheritance
class diagram of sum of an A.P. series Multiple Inheritance

Output

Input the starting number: 2

Input the number of items: 4

Input the common difference: 6

the Sum of the A.P. series are :

2+8+14+20=44