It's impossible to read without code tags and formatting:
[code]
// paste code here
[/code]
You have some stray brackets in there, which I assume is an attempt to post with code tags, but I'm not sure. If they are in the code itself, delete them. Start by commenting everything out in main except for return 0;
See if it compiles then. Start uncommenting a line at a time in main till you get an error. This error here:undefined reference to `screen::screen()'
suggests that you have a definite problem in your Screen class, which you said was OK. In particular, make sure it can compile these two lines in the beginning of main.
screen S;
Brush B;
This error suggests that you won't get past the first line above.undefined reference to `screen::screen()'
You can temporarily make everything public too and see if that helps, but I doubt that's the problem, so save it for later. Uncomment main one line at a time from the top till you get your first error. Ignore the other errors, fix the first, then try again. Also, repost with code tags please.