The entire programming exercise is supposed to find the distance between two points in 3D space. Every file that is included is necessary per instructor guidelines. I have fixed everything down to 5 seemingly simple errors:
Yup. In case you don't know (because protected is that funny third label), protected means that if I had an object of derived and an object of base, and the base had protected stuff, the derived objects could access the protected stuff. But the general user would still not be able to get at it.
I cannot believe that I missed that #include statement. I typed that in, removed the friend class statement, and put the necessary variables in protected status, and IT WORKS!