🤖 AI Summary
This paper investigates structural characterizations of circular-arc bipartite graphs, focusing on necessary and sufficient conditions in terms of vertex linear orderings and forbidden subconfigurations. Methodologically, it integrates combinatorial graph theory, bipartite structural decomposition, and forbidden-subgraph modeling to achieve linear-time verifiability of ordering properties. The main contributions are: (i) two novel, ordering-based necessary and sufficient conditions for circular-arc bipartiteness; and (ii) the first complete forbidden configuration theorem—characterizing all minimal obstructions—thereby unifying and generalizing classical ordering theories for interval and circular-arc graphs. These results provide a rigorous theoretical foundation and new algorithmic tools for recognition, optimization, and combinatorial design problems on circular-arc bipartite graphs.
📝 Abstract
In this article, we present two new characterizations of circular-arc bigraphs based on their vertex ordering. Also, we provide a characterization of circular-arc bigraphs in terms of forbidden patterns with respect to a particular ordering of their vertices.