Define a class named EvenCounter. It should have a public instance method named addValue taking a single Int argument. If the argument passed to addValue is even, it increments the count stored by the counter. addValue does not return a value. Your count property should be publicly readable but not publicly writable. Your class should also provide a constructor taking a single Int argument that sets the initial count, which you should assert is non-negative. Your class should not allow modifications to the count except using the addValue method.

When you are finished your class should work as follows: