Abstract
We give a complexity dichotomy for the Quantified Constraint Satisfaction Problem QCSP(H) when H is a reflexive tournament. It is well-known that reflexive tournaments can be split into a sequence of strongly connected components H1,..., Hn so that there exists an edge from every vertex of Hi to every vertex of Hj if and only if i < j. We prove that if H has both its initial and final strongly connected component (possibly equal) of size 1, then QCSP(H) is in NL and otherwise QCSP(H) is NP-hard.
Original language | English |
---|---|
Title of host publication | 29th Annual European Symposium on Algorithms, ESA 2021 |
Editors | Petra Mutzel, Rasmus Pagh, Grzegorz Herman |
Publisher | Schloss Dagstuhl- Leibniz-Zentrum fur Informatik GmbH, Dagstuhl Publishing |
ISBN (Electronic) | 9783959772044 |
DOIs | |
Publication status | Published - 1 Sept 2021 |
Event | 29th Annual European Symposium on Algorithms, ESA 2021 - Vitual, Lisbon, Portugal Duration: 6 Sept 2021 → 8 Sept 2021 |
Publication series
Name | Leibniz International Proceedings in Informatics, LIPIcs |
---|---|
Volume | 204 |
ISSN (Print) | 1868-8969 |
Conference
Conference | 29th Annual European Symposium on Algorithms, ESA 2021 |
---|---|
Country/Territory | Portugal |
City | Vitual, Lisbon |
Period | 6/09/21 → 8/09/21 |
Bibliographical note
Funding Information:Stanislav Živný: Stanislav Zivny was supported by a Royal Society University Research Fellowship. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 714532). The paper reflects only the authors' views and not the views of the ERC or the European Commission. The European Union is not liable for any use that may be made of the information contained therein.
Funding Information:
Funding Stanislav Živný: Stanislav Zivny was supported by a Royal Society University Research Fellowship. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 714532). The paper reflects only the authors’ views and not the views of the ERC or the European Commission. The European Union is not liable for any use that may be made of the information contained therein.
Publisher Copyright:
© Benoît Larose, Petar Marković, Barnaby Martin, Daniël Paulusma, Siani Smith, and Stanislav Živný; licensed under Creative Commons License CC-BY 4.0
Keywords
- Algorithmic graph theory
- Computational complexity
- Constraint satisfaction
- Quantified constraints
- Universal algebra