Exploration of Graphs with Excluded Minors

Authors Júlia Baligács , Yann Disser , Irene Heinrich , Pascal Schweitzer

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Júlia Baligács
  • Technische Universität Darmstadt, Germany
Yann Disser
  • Technische Universität Darmstadt, Germany
Irene Heinrich
  • Technische Universität Darmstadt, Germany
Pascal Schweitzer
  • Technische Universität Darmstadt, Germany

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Júlia Baligács, Yann Disser, Irene Heinrich, and Pascal Schweitzer. Exploration of Graphs with Excluded Minors. In 31st Annual European Symposium on Algorithms (ESA 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 274, pp. 11:1-11:15, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)


We study the online graph exploration problem proposed by Kalyanasundaram and Pruhs (1994) and prove a constant competitive ratio on minor-free graphs. This result encompasses and significantly extends the graph classes that were previously known to admit a constant competitive ratio. The main ingredient of our proof is that we find a connection between the performance of the particular exploration algorithm Blocking and the existence of light spanners. Conversely, we exploit this connection to construct light spanners of bounded genus graphs. In particular, we achieve a lightness that improves on the best known upper bound for genus g ≥ 1 and recovers the known tight bound for the planar case (g = 0).

Subject Classification

ACM Subject Classification
  • Theory of computation → Online algorithms
  • Theory of computation → Sparsification and spanners
  • Mathematics of computing → Graphs and surfaces
  • online algorithms
  • competitive analysis
  • graph exploration
  • graph spanners
  • minor-free graphs
  • bounded genus graphs


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