+ Propose a 2D matrix of pixels to represent the screen. + Distinguish between a four way (left, right, up, down) fill, and an eight way fill (previous 4 ways + diagonals) + Clarify the use of colors, B/W or use an enum for the supported colors, etc. Then do it recursively or iteratively, by painting a pixel or ignoring it. If painting a pixel, repeat for its adjacent pixels, otherwise, return.