Figure 6
From: Systematic benchmark of substructure search in molecular graphs - From Ullmann to VF2
VF2 feasibility rule for node cardinality (1-look-ahead). VF2 feasibility rule for node cardinality (1-look-ahead). The rule prohibits an extension of the current solution M(s) by candidates with a substructure cardinality that can not be fully mapped onto the graph. In the given example, node m has one edge into T2(s) and is mapped to atom n with a cardinality of two. Therefore, the mapping is feasible.