“…Because graphs are non-linear data structures [20], [21] they are a challenging and interesting research area that can be used to organize, simulate, model and solve a lot of real world problems [22], [23], [24] and thus it has become more popular both in scientific as well as commercial fields. Graph analysis [25] has been studied for a long time, and is the premise for many applications such as those associated with social networks, telephone networks, program flows, bio-informatics, chemical compounds, terrorist networks, etc., with closed frequent subgraph mining forming the fundamental basis for graph clustering, graph based anomaly detection, and graph classification [26], [27], [28].…”