17.7) Exercise 26

Write a header file called circle.hpp, defining a class called Circle.

Give your class:

• Private instance variables called centre_x and centre_y, of type double, representing the position of the circle’s centre
• A private instance variable called radius, of type double, representing the circle’s radius
• A constructor that will accept initial values for the three instance variables
• Methods get_x, get_y and get_radius that each have no parameters and return a double value
• Methods area and circumference that each have no parameters and return a double

Remember that you are writing method prototypes here, not implementations!