Box of 2 or 3 (584)

Draw some “boxes” (not necessarily rectangular) around the dots so that each box contains exactly 2 or 3 dots. No dot may be in more than one box (but some dots might be in zero boxes). Each black dot must be in a box. Each white dot may be in a box, but does not have to be. All dots within a box must be connected to each other via line segments within the box, either directly or indirectly. Line segments that connect dots (of any color) belonging to two different boxes must connect boxes of different sizes (that is, a size-2 box and a size-3 box).

Reference: WPF (1)