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Exploiting New Types of Structure for Fixed Parameter Tractability (Research Project)

Funding Organisation: The Austrian Science Funds, FWF
Project Number: FWF P26696

Project Team

Eduard Eiben (Doctoral Student)
Robert Ganian (Postdoc, Project Coordinator)
Ramanujan Sridharan (Postdoc)
Stefan Szeider (Professor, Principal Investigator)

Topic

Many important computational problems are intractable on general instances. However, realistic problem instances often contain a certain hidden structure that can be exploited to solve the problem efficiently. Such instances form a tractable class (or an island of tractability). Previous research has identified a large number of tractable classes for various NP-hard problems.

The aim of this project is to develop a rigorous framework for exploiting new kinds of structure on a wide range of problem inputs; in particular, this framework will be based on the established notion of a modulator to a tractable class of instances, which applies to problem instances that may be placed in a tractable class by a small number of local changes. The type of structure exploited by algorithms developed within the proposed research is fundamentally different from the structure exploited by known state-of-the-art approaches. This will allow us to handle natural instances where all presently known state-of-the-art approaches remain unfeasible.

Publications

2018

7 results
2018
[7]The complexity landscape of decompositional parameters for ILP
Robert Ganian, Sebastian Ordyniak
Artificial Intelligence, volume 257, pages 61–71, 2018.
[bibtex] [pdf]
[6]Meta-kernelization using well-structured modulators
Eduard Eiben, Robert Ganian, Stefan Szeider
Discr. Appl. Math., volume 248, pages 153–167, 2018.
[bibtex] [pdf] [doi]
[5]Solving Problems on Graphs of High Rank-Width
Eduard Eiben, Robert Ganian, Stefan Szeider
Algorithmica, volume 80, number 2, pages 742–771, 2018.
[bibtex] [pdf] [doi]
[4]On the complexity of rainbow coloring problems
Eduard Eiben, Robert Ganian, Juho Lauri
Discr. Appl. Math., volume 246, pages 38–48, 2018.
[bibtex] [pdf]
[3]A single-exponential fixed-parameter algorithm for distance-hereditary vertex deletion
Eduard Eiben, Robert Ganian, O-joung Kwon
Journal of Computer and System Sciences, volume 97, pages 121–146, 2018.
[bibtex] [pdf]
[2]On Structural Parameterizations of the Bounded-Degree Vertex Deletion Problem
Robert Ganian, Fabian Klute, Sebastian Ordyniak
35th Symposium on Theoretical Aspects of Computer Science, STACS 2018, February 28–March 3, 2018, Caen, France (Rolf Neidermeier, Brigitte Vallée, eds.), volume 96 of LIPIcs, pages 33:1–33:14, 2018, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf]
[1]Small Resolution Proofs for QBF using Dependency Treewidth
Eduard Eiben, Robert Ganian, Sebastian Ordyniak
35th Symposium on Theoretical Aspects of Computer Science, STACS 2018, February 28–March 3, 2018, Caen, France (Rolf Neidermeier, Brigitte Vallée, eds.), volume 96 of LIPIcs, pages 28:1–28:15, 2018, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf]

2017

16 results
2017
[16]On the parameterized complexity of finding small unsatisfiable subsets of CNF formulas and CSP instances
Ronald de Haan, Iyad Kanj, Stefan Szeider
ACM Transactions on Computational Logic, volume 18, number 3, pages Art. 21, 46, 2017.
[bibtex] [pdf] [doi]
[15]Discovering Archipelagos of Tractability for Constraint Satisfaction and Counting
Robert Ganian, M. S. Ramanujan, Stefan Szeider
ACM Transactions on Algorithms, volume 13, number 2, pages 29:1–29:32, 2017.
[bibtex] [pdf] [doi]
[14]A Linear-Time Parameterized Algorithm for Node Unique Label Cover
Daniel Lokshtanov, M. S. Ramanujan, Saket Saurabh
25th Annual European Symposium on Algorithms (ESA 2017) (Kirk Pruhs, Christian Sohler, eds.), volume 87 of Leibniz International Proceedings in Informatics (LIPIcs), pages 57:1–57:15, 2017, Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf] [doi]
[13]Rigging Nearly Acyclic Tournaments Is Fixed-Parameter Tractable
M. S. Ramanujan, Stefan Szeider
Proceedings of the Thirty-First AAAI Conference on Artificial Intelligence, February 4-9, 2017, San Francisco, California, USA, pages 3929–3935, 2017.
[bibtex] [pdf]
[12]Linear Representation of Transversal Matroids and Gammoids parameterized by rank
Fahad Panolan, Pranabendu Misra, M. S. Ramanujan, Saket Saurabh
Computing and Combinatorics: 23rd International Conference, COCOON 2017, Hong Kong, China, August 3-5, 2017, Proceedings (Yixin Cao, Jianer Chen, eds.), pages 420–432, 2017, Springer Verlag.
[bibtex] [pdf] [doi]
[11]Lossy kernelization
Daniel Lokshtanov, Fahad Panolan, M. S. Ramanujan, Saket Saurabh
Proceedings of the 49th Annual ACM SIGACT Symposium on Theory of Computing, STOC 2017, Montreal, QC, Canada, June 19-23, 2017, pages 224–237, 2017.
[bibtex] [pdf] [doi]
[10]New Width Parameters for Model Counting
Robert Ganian, Stefan Szeider
Theory and Applications of Satisfiability Testing - SAT 2017 - 20th International Conference, Melbourne, VIC, Australia, August 28 - September 1, 2017, Proceedings (Serge Gaspers, Toby Walsh, eds.), volume 10491 of Lecture Notes in Computer Science, pages 38–52, 2017, Springer Verlag.
[bibtex] [pdf] [doi]
[9]Backdoor Treewidth for SAT
Robert Ganian, M. S. Ramanujan, Stefan Szeider
Theory and Applications of Satisfiability Testing - SAT 2017 - 20th International Conference, Melbourne, VIC, Australia, August 28 - September 1, 2017, Proceedings (Serge Gaspers, Toby Walsh, eds.), volume 10491 of Lecture Notes in Computer Science, pages 20–37, 2017, Springer Verlag.
[bibtex] [pdf] [doi]
[8]Combining Treewidth and Backdoors for CSP
Robert Ganian, M. S. Ramanujan, Stefan Szeider
34th Symposium on Theoretical Aspects of Computer Science (STACS 2017) (Heribert Vollmer, Vallée, eds.), volume 66 of Leibniz International Proceedings in Informatics (LIPIcs), pages 36:1–36:17, 2017, Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf] [doi]
[7]On Structural Parameterizations of the Edge Disjoint Paths Problem
Robert Ganian, Sebastian Ordyniak, Ramanujan Sridharan
28th International Symposium on Algorithms and Computation, ISAAC 2017, December 9-12, 2017, Phuket, Thailand (Yoshio Okamoto, Takeshi Tokuyama, eds.), volume 92 of LIPIcs, pages 36:1–36:13, 2017, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf]
[6]Path-Contractions, Edge Deletions and Connectivity Preservation
Gregory Gutin, M. S. Ramanujan, Felix Reidl, Magnus Wahlström
25th Annual European Symposium on Algorithms (ESA 2017) (Kirk Pruhs, Christian Sohler, eds.), volume 87 of Leibniz International Proceedings in Informatics (LIPIcs), pages 47:1–47:13, 2017, Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf] [doi]
[5]SAT-Based Local Improvement for Finding Tree Decompositions of Small Width
Johannes K. Fichte, Neha Lodha, Stefan Szeider
Theory and Applications of Satisfiability Testing - SAT 2017 - 20th International Conference, Melbourne, VIC, Australia, August 28 - September 1, 2017, Proceedings (Serge Gaspers, Toby Walsh, eds.), volume 10491 of Lecture Notes in Computer Science, pages 401–411, 2017, Springer Verlag.
[bibtex] [pdf] [doi]
[4]Solving Integer Linear Programs with a Small Number of Global Variables and Constraints
Pavel Dvořák, Eduard Eiben, Robert Ganian, Dušan Knop, Sebastian Ordyniak
Proceedings of the Twenty-Sixth International Joint Conference on Artificial Intelligence, IJCAI 2017, Melbourne, Australia, August 19-25, 2017 (Carles Sierra, ed.), pages 607–613, 2017, ijcai.org.
[bibtex] [pdf]
[3]Going Beyond Primal Treewidth for (M)ILP
Robert Ganian, Sebastian Ordyniak, M. S. Ramanujan
Proceedings of the Thirty-First AAAI Conference on Artificial Intelligence, February 4-9, 2017, San Francisco, California, USA., pages 815–821, 2017.
[bibtex] [pdf]
[2]Saving Critical Nodes with Firefighters is FPT
Jayesh Choudhari, Anirban Dasgupta, Neeldhara Misra, M. S. Ramanujan
44th International Colloquium on Automata, Languages, and Programming (ICALP 2017) (Ioannis Chatzigiannakis, Piotr Indyk, Fabian Kuhn, Anca Muscholl, eds.), volume 80 of Leibniz International Proceedings in Informatics (LIPIcs), pages 135:1–135:13, 2017, Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf] [doi]
[1]Towards a Polynomial Kernel for Directed Feedback Vertex Set
Benjamin Bergougnoux, Eduard Eiben, Robert Ganian, Sebastian Ordyniak, M. S. Ramanujan
42nd International Symposium on Mathematical Foundations of Computer Science, MFCS 2017, August 21-25, 2017 - Aalborg, Denmark (Kim G. Larsen, Hans L. Bodlaender, Jean-François Raskin, eds.), volume 83 of LIPIcs, pages 36:1–36:15, 2017, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf]

2016

18 results
2016
[18]Backdoors to q-Horn
Serge Gaspers, Sebastian Ordyniak, M. S. Ramanujan, Saket Saurabh, Stefan Szeider
Algorithmica, volume 74, number 1, pages 540–557, 2016.
[bibtex] [pdf] [doi]
[17]Meta-Kernelization with Structural Parameters
Robert Ganian, Friedrich Slivovsky, Stefan Szeider
Journal of Computer and System Sciences, volume 82, number 2, pages 333–346, 2016.
[bibtex] [pdf] [doi]
[16]FO Model Checking of Interval Graphs
Robert Ganian, Petr Hlinený, Daniel Král, Jan Obdrzálek, Jarett Schwartz, Jakub Teska
Logical Methods in Computer Science, volume 11, number 4, 2016.
[bibtex] [pdf]
[15]Quantified Conjunctive Queries on Partially Ordered Sets
Simone Bova, Robert Ganian, Stefan Szeider
Theoretical Computer Science, volume 618, pages 72–84, 2016.
[bibtex] [pdf] [doi]
[14]A Faster Parameterized Algorithm for Group Feedback Edge Set
M. S. Ramanujan
Graph-Theoretic Concepts in Computer Science - 42nd International Workshop, WG 2016, Istanbul, Turkey, June 22-24, 2016, Revised Selected Papers, pages 269–281, 2016.
[bibtex] [pdf]
[13]A Parameterized Algorithm for Mixed-Cut
Ashutosh Rai, M. S. Ramanujan, Saket Saurabh
LATIN 2016: Theoretical Informatics - 12th Latin American Symposium, Ensenada, Mexico, April 11-15, 2016, Proceedings, pages 672–685, 2016.
[bibtex] [pdf]
[12]Strong Parameterized Deletion: Bipartite Graphs
Ashutosh Rai, M. S. Ramanujan
36th IARCS Annual Conference on Foundations of Software Technology and Theoretical Computer Science, FSTTCS 2016, December 13-15, 2016, Chennai, India, pages 21:1–21:14, 2016.
[bibtex] [pdf] [doi]
[11]Backdoors for Linear Temporal Logic
Arne Meier, Sebastian Ordyniak, Ramanujan Sridharan, Irena Schindler
11th International Symposium on Parameterized and Exact Computation (IPEC 2016) (Jiong Guo, Danny Hermelin, eds.), volume 63 of Leibniz International Proceedings in Informatics (LIPIcs), pages 23:1–23:17, 2016, Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf] [doi]
[10]Backdoors to Tractable Valued CSP
Robert Ganian, M.S. Ramanujan, Stefan Szeider
Principles and Practice of Constraint Programming - 22nd International Conference, CP 2016, Toulouse, France, September 5-9, 2016, Proceedings (Michel Rueher, ed.), volume 9892 of Lecture Notes in Computer Science, pages 233–250, 2016, Springer Verlag.
[bibtex] [pdf] [doi]
[9]Discovering Archipelagos of Tractability for Constraint Satisfaction and Counting
Robert Ganian, M. S. Ramanujan, Stefan Szeider
Proceedings of the Twenty-Seventh Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2016, Arlington, VA, USA, January 10-12, 2016, pages 1670–1681, 2016.
[bibtex] [pdf] [doi]
[8]The Complexity Landscape of Decompositional Parameters for ILP
Robert Ganian, Sebastian Ordyniak
Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence (Dale Schuurmans, Michael P. Wellman, eds.), pages 710–716, 2016, AAAI Press.
[bibtex] [pdf]
[7]Polynomial-Time Construction of Optimal MPI Derived Datatype Trees
Robert Ganian, Martin Kalany, Stefan Szeider, Jesper Larsson Träff
2016 IEEE International Parallel and Distributed Processing Symposium, IPDPS 2016, Chicago, IL, USA, May 23-27, 2016, pages 638–647, 2016, IEEE Computer Society.
[bibtex] [pdf] [doi]
[6]On Existential MSO and its Relation to ETH
Robert Ganian, Ronald de Haan, Iyad Kanj, Stefan Szeider
41st International Symposium on Mathematical Foundations of Computer Science (MFCS 2016) (Piotr Faliszewski, Anca Muscholl, Rolf Niedermeier, eds.), volume 58 of Leibniz International Proceedings in Informatics (LIPIcs), pages 42:1–42:14, 2016, Schloss Dagstuhl–Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf] [doi]
[5]A New Perspective on FO Model Checking of Dense Graph Classes
Jakub Gajarský, Petr Hlinený, Jan Obdrzálek, Daniel Lokshtanov, M. S. Ramanujan
Proceedings of the 31st Annual ACM/IEEE Symposium on Logic in Computer Science, LICS '16, New York, NY, USA, July 5-8, 2016, pages 176–184, 2016.
[bibtex] [pdf]
[4]On the Complexity Landscape of Connected f-factor Problems
Robert Ganian, N.S. Narayanaswamy, Sebastian Ordyniak, C.S. Rahul, Ramanujan M. S.
Mathematical Foundations of Computer Science 2016 - 41st International Symposium, MFCS 2016 (Piotr Faliszewski, Anca Muscholl, Rolf Niedermeier, eds.), pages 41:1–41:14, 2016, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf]
[3]Counting Linear Extensions: Parameterizations by Treewidth
Eduard Eiben, Robert Ganian, Kustaa Kangas, Sebastian Ordyniak
24th European Symposium of Algorithms, ESA 2016, volume 57 of LIPIcs, pages 39:1–39:18, 2016, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf]
[2]Using Decomposition-Parameters for QBF: Mind the Prefix!
Eduard Eiben, Robert Ganian, Sebastian Ordyniak
Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence (Dale Schuurmans, Michael P. Wellman, eds.), pages 964–970, 2016, AAAI Press.
[bibtex] [pdf]
[1]A Single-Exponential Fixed-Parameter Algorithm for Distance-Hereditary Vertex Deletion
Eduard Eiben, Robert Ganian, O-joung Kwon
Mathematical Foundations of Computer Science 2016 - 41st International Symposium, MFCS 2016 (Piotr Faliszewski, Anca Muscholl, Rolf Niedermeier, eds.), volume 58 of LIPIcs, pages 34:1–34:14, 2016, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik.
[bibtex] [pdf]

2015

6 results
2015
[6]Community Structure Inspired Algorithms for SAT and #SAT
Robert Ganian, Stefan Szeider
18th International Conference on Theory and Applications of Satisfiability Testing (SAT 2015), September 24-27, 2015, Austin, Texas (Marijn Heule, Sean Weaver, eds.), pages 223-237, 2015, Springer Verlag.
[bibtex] [pdf] [doi]
[5]Parameterized Complexity of Asynchronous Border Minimization
Robert Ganian, Martin Kronegger, Andreas Pfandler, Alexandru Popa
Theory and Applications of Models of Computation - 12th Annual Conference, TAMC 2015, Singapore, May 18-20, 2015, Proceedings (Rahul Jain, Sanjay Jain, Frank Stephan, eds.), volume 9076 of Lecture Notes in Computer Science, pages 428–440, 2015, Springer Verlag.
[bibtex] [pdf] [doi]
[4]Algorithmic Applications of Tree-Cut Width
Robert Ganian, Eun Jung Kim, Stefan Szeider
Mathematical Foundations of Computer Science 2015 - 40th International Symposium, MFCS 2015, Milan, Italy, August 24-28, 2015, Proceedings, Part II, volume 9235 of Lecture Notes in Computer Science, pages 348–360, 2015, Springer Verlag.
[bibtex] [pdf] [doi]
[3]Meta-Kernelization using Well-Structured Modulators
Eduard Eiben, Robert Ganian, Stefan Szeider
Parameterized and Exact Computation - 10th International Symposium, IPEC 2014, Patras, Greece, September 16-18, 2015. Revised Selected Papers (Thore Husfeldt, Iyad A. Kanj, eds.), volume 43 of LIPIcs, pages 114–126, 2015.
[bibtex] [pdf] [doi]
[2]Solving Problems on Graphs of High Rank-Width
Eduard Eiben, Robert Ganian, Stefan Szeider
Algorithms and Data Structures Symposium (WADS 2015), August 5-7, 2015, University of Victoria, BC, Canada, pages 314–326, 2015, Springer Verlag.
[bibtex] [pdf] [doi]
[1]On the Complexity of Rainbow Coloring Problems
Eduard Eiben, Robert Ganian, Juho Lauri
Combinatorial Algorithms - 26th International Workshop, IWOCA 2015, Verona, Italy, October 5-7, 2015, Revised Selected Papers (Zsuzsanna Lipták, William F. Smyth, eds.), pages 209–220, 2015.
[bibtex] [pdf] [doi]

2014

1 result
2014
[1]Quantified Conjunctive Queries on Partially Ordered Sets
Simone Bova, Robert Ganian, Stefan Szeider
Parameterized and Exact Computation - 9th International Symposium, IPEC 2014, Wroclaw, Poland, September 10-12, 2014. Revised Selected Papers (Marek Cygan, Pinar Heggernes, eds.), volume 8894 of Lecture Notes in Computer Science, pages 122–134, 2014, Springer Verlag.
[bibtex] [pdf] [doi]

News

  • Best Paper Award at SOFSEM 2025

    Best Paper Award at SOFSEM 2025

    2025-01-23
    Thomas Depian, Simon D. Fink, Alexander Firbas, Robert Ganian, and Martin Nöllenburg received the Best Paper Award for their paper …Read More »
  • Markus Wallinger receives Award of Excellence for his PhD Thesis

    Markus Wallinger receives Award of Excellence for his PhD Thesis

    2024-12-05
    Our former group member Markus Wallinger won the Award of Excellence by the Federal Ministry for Education, Science and Research. …Read More »
  • Thomas Depian receives State Prize for his Master’s Thesis

    Thomas Depian receives State Prize for his Master’s Thesis

    2024-11-21
    Our group member Thomas Depian won the Appreciation Award given by the Federal Ministry for Education, Science and Research. This …Read More »
  • Best Paper Award at GECCO 2024 for M. Bresich, G. Raidl, and S. Limmer

    Best Paper Award at GECCO 2024 for M. Bresich, G. Raidl, and S. Limmer

    2024-07-24
    Maria Bresich, Günther Raidl, and Steffen Limmer received the best paper award at the 2024 Genetic and Evolutionary Computation Conference …Read More »
  • Welcome to our Feodor Lynen Fellow Dr. Frank Sommer

    Welcome to our Feodor Lynen Fellow Dr. Frank Sommer

    2024-06-14
    On June 1, 2024, Dr. Frank Sommer has joined the Algorithms and Complexity group with a prestigious Feodor Lynen postdoc …Read More »

News archive

All news for 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023 and 2024.
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