0 superclusters: () : adding (0)... 0 intersections.
1 supercluster: ((0)) : adding (1,2,3)... 0 intersections.
2 superclusters: ((0), (1,2,3)) : adding (0,1)... 2 intersections.
1 supercluster: ((0,1,2,3)) : adding (0,1,2)... 1 intersection.