Linear-Time Graph Programs for Unbounded-Degree Graphs
Achieving the complexity of graph algorithms in conventional languages with programs based on graph transformation rules is challenging because of the cost of graph matching. Previous work demonstrated that with so-called rooted rules, certain algorithms can be executed in linear time using the graph programming language GP 2. However, for non-destructive algorithms which retain the structure of input graphs, achieving a linear runtime required that input graphs have a bounded node degree. In this paper, we show how to overcome this restriction by enhancing the graph data structure generated by the GP 2 compiler and exploiting the new structure in programs. As a case study, we present a 2-colouring program that runs in linear time on arbitrary input graphs. We prove the linear time complexity and also provide empirical evidence in the form of timings for various classes of input graphs. In addition, we give experimental evidence for the linear runtime of a program checking graphs for connectedness.
Thu 11 JulDisplayed time zone: Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna change
13:30 - 15:00 | |||
13:30 30mTalk | A Graph Transformation-Based Engine for the Automated Exploration of Constraint Models ICGT Research Papers P: Christopher Stone University of St Andrews, AndrĂ¡s Z. Salamon University of St Andrews, Ian Miguel University of St Andrews | ||
14:00 30mTalk | Graph Algebras and Derived Graph OperationsJournal-first paper ICGT Research Papers Link to publication DOI | ||
14:30 30mTalk | Linear-Time Graph Programs for Unbounded-Degree Graphs ICGT Research Papers P: Ziad Ismaili Alaoui Department of Computer Science, University of York, Detlef Plump University of York |