Scope
The International Symposium on Parameterized and Exact Computation (IPEC) is an annual conference covering all aspects of parameterized and exact algorithms and complexity. Its 20th edition will be part of ALGO 2025, which also hosts ESA 2025 and other specialized conferences and workshops. We are excited that ALGO 2025 is planned as an in-person conference and we look forward to seeing you there!
Important Dates
- Abstract submission / paper registration: June 27th (23:59 AoE)
- Submission deadline: June 30th (23:59 AoE)
- Notification: August 7th (AoE)
- IPEC dates: Sept. 17—19 (Wed-Fri)
- Camera-ready version: October 10th (23:59 AoE)
AoE=Anywhere on Earth (UTC-12)
Invited talks
The IPEC 2025 keynote/invited tutorial will be given by Martin Koutecky (Charles University, Prague). There will also be a keynote talk by the 2025 EATCS-IPEC Nerode Prize winner(s): Jaroslav Nešetřil and Patrice Ossona de Mendez.
Accepted Papers
- A Graph Width Perspective on Partially Ordered Hamiltonian Paths and Cycles II, Vertex and Edge Deletion Numbers
Jesse Beisegel, Katharina Klost, Kristin Knorr, Fabienne Ratajczak and Robert Scheffler - A Note on the Parameterised Complexity of Coverability in Vector Addition Systems
Michał Pilipczuk, Sylvain Schmitz and Henry Sinclair-Banks - A polynomial delay algorithm generating all potential maximal cliques in triconnected planar graphs
Alexander Grigoriev, Yasuaki Kobayashi, Hisao Tamaki and Tom van der Zanden - A simple algorithm for Combinatorial n-fold ILPs using the Steinitz Lemma
Sushmita Gupta, Pallavi Jain, Sanjay Seetharaman and Meirav Zehavi - An ETH-Tight FPT Algorithm for Rejection-Proof Set Packing with Applications to Kidney Exchange
Bart M. P. Jansen, Jeroen S. K. Lamme and Ruben F. A. Verhaegh - Binary k-Center with Missing Entries, Structure Leads to Tractability
Tobias Friedrich, Kirill Simonov and Farehe Soheil - Boundaried Kernelization via Representative Sets
Leonid Antipov and Stefan Kratsch - Bridging Treewidth and Clique-width via Cograph-Modular-Treewidth
Satyabrata Jana, Peter Strulo, Václav Blažej and M. S. Ramanujan - Complexity of Local Search for CSPs Parameterized by Constraint Difference
Aditya Anand, Vincent Cohen-Addad, Tommaso D’Orsi, Anupam Gupta, Euiwoong Lee, Debmalya Panigrahi and Sijin Peng - Designing Compact ILPs via Fast Witness Verification
Michał Włodarczyk - Deterministically counting k-paths and trees parameterized by treewidth in single-exponential time
Jonne Visser and Hans Bodlaender - Directed disjoint paths remains W[1]-hard on acyclic digraphs without large grid minors
Marcelo Garlet Milani, Ken-Ichi Kawarabayashi, Jacob Stegemann and Nicola Lorenz - Efficient Enumeration of Quasi-Cliques
George Manoussakis and Mohamed Jiddou - Enumeration kernels for Vertex Cover and Feedback Vertex Set
Marin Bougeret, Guilherme de Castro Mendes Gomes, Vinicius F. dos Santos and Ignasi Sau - Exact Algorithms and Hardness Result for the Boolean Connectivity Problem of k-Horn Formulas
Takashi Horiyama, Yuto Okura, Kazuhisa Seto and Junichi Teruyama - Geodetic Set on Graphs of Constant Pathwidth and Feedback Vertex Set Number
Prafullkumar Tale - Hamiltonicity Parameterized by Mim-Width is (Indeed) Para-NP-Hard
Benjamin Bergougnoux and Lars Jaffke - Hitting Geodesic Intervals in Structurally Restricted Graphs
Tatsuya Gima, Yasuaki Kobayashi, Yuto Okada, Yota Otachi and Hayato Takaike - Kernelization for H-Coloring (Best paper award)
Yael Berkman and Ishay Haviv - New Algorithm for Combinatorial n-folds and Applications
Klaus Jansen, Kai Kahler, Lis Pirotton and Malte Tutas - On maximum 2-clubs
Joanne Dumont, Michael Lampis, Mathieu Liedloff, Anthony Perez and Ioan Todinca - On the Complexity of Secluded Path Problems
Tesshu Hanaka and Daisuke Tsuru - Parameterized Algorithms for Diversity of Networks with Ecological Dependencies
Mark Jones and Jannik Schestag - Parameterized complexity of scheduling unit-time jobs with generalized precedence constraints
Christina Büsing, Maurice Draeger and Corinna Mathwieser - Parameterized Complexity of Vehicle Routing
Michelle Döring, Jan Fehse, Tobias Friedrich, Paula Marten, Niklas Mohrin, Kirill Simonov, Farehe Soheil, Jakob Timm and Shaily Verma - Parameterized Maximum Node-Disjoint Paths
Michael Lampis and Manolis Vasilakis - Tight bounds for Connected Odd Cycle Transversal parameterized by clique-width
Narek Bojikian and Stefan Kratsch - Timeline Problems in Temporal Graphs, Vertex Cover vs. Dominating Set
Anton Herrmann, Christian Komusiewicz, Nils Morawietz and Frank Sommer - Treedepth Inapproximability and Exponential ETH Lower Bound
Édouard Bonnet, Daniel Neuen and Marek Sokołowski - Uniformity within Parameterized Circuit Classes
Steef Hegeman, Jan Martens and Alfons Laarman
Call for Papers
The 20th International Symposium on Parameterized and Exact Computation (IPEC 2025) invites papers presenting original research in the area of parameterized and exact algorithms and complexity.
Papers can be submitted via Easychair: https://easychair.org/conferences/?conf=ipec2025 (please see submission and coi guidelines below).
Topics
The topics include but are not limited to:
- new techniques for the design and analysis of parameterized and exact algorithms;
- fixed-parameter tractability and kernelization results;
- parameterized complexity theory;
- parameterized (in)approximability results;
- relationships between parameterized complexity and traditional complexity classifications;
- applications of parameterized and exact computation;
- engineering and experimentation of exact, parameterized, and kernelization algorithms.
Submission Guidelines
Each submission is required to be in the LIPIcs format; no changes to font size, page margins, etc., are permitted. Line numbers must be activated. We welcome submissions of the full version of the paper. Regardless, the first 12 pages of the submission (excluding the title page) should be enough to assess the paper and contain a summary of the main results, their motivation and importance, and evidence of their correctness. In particular, PC members and potential subreviewers may treat the first 12 pages as the short version (the rest being read at their discretion).
Results previously published in conference proceedings or a journal (or scheduled for publication prior to IPEC) or under simultaneous submission will not be considered.
PC members (outside the PC chairs) are allowed to author or coauthor submissions.
Double-blind reviewing: As in previous years, IPEC 2025 employs a lightweight double-blind reviewing process. Submissions should not reveal the identity of the authors in any way. In particular, authors’ names, affiliations, and email addresses should not appear at the beginning or in the body of the submission. Authors should ensure that any references to their own related work is in the third person (e.g., not “We build on our previous work …” but rather “We build on the work of …”). The purpose of the double-blind reviewing is to help PC members and external reviewers come to an initial judgement about the paper without bias, not to make it impossible for them to discover the authors if they were to try. Nothing should be done in the name of anonymity that weakens the submission or makes the job of reviewing the paper more difficult. In particular, important references should not be omitted or anonymized. In addition, authors should feel free to disseminate their ideas or draft versions of their paper as they normally would. For example, authors may post drafts of their papers on the web, submit them to arXiv, and give talks on their research ideas. In case there exist publicly available versions of the submission online, the authors might mention this in their submission (without providing references/links), and briefly explain the differences if any. Alternatively, they might communicate the details to the chairs, who will keep them confidential unless revealing them to the PC is needed for a fair judgement. Authors with further questions on double-blind reviewing are encouraged to contact the PC chairs.
Conflicts of Interest
IPEC takes conflicts of interest, both real and perceived, seriously. Authors are responsible for declaring conflicts of interest with any of the PC members. You have a conflict of interest with:
- family members and close friends;
- Ph.D. advisor or advisee (no time limit), or postdoc or undergraduate mentor or mentee within the past 5 years;
- people with the same affiliation;
- involved in an alleged incident of harassment (it is not required that the incident be reported);
- reviewer owes author a favor (e.g., recently requested a reference letter); and
- frequent or recent collaborator whom you believe cannot objectively review your work.
Submission link
Submissions via EasyChair: https://easychair.org/conferences/?conf=ipec2025
Conference and Paper Publication
Authors of accepted papers are expected to present their work at the symposium, and to incorporate the comments from the program committee. The conference proceedings will be published in the Leibniz International Proceedings in Informatics (LIPIcs) series after the conference (post-proceedings).
The final submission will be made in LIPIcs format, with a higher page limit of 15 pages plus bibliography (no appendix). More details will follow from LIPIcs upon acceptance. The submissions will be published as post-proceedings.
Awards
A best paper award and a best student paper award may be conferred. All submissions are eligible for the best paper award, except submissions co-authored by PC members. Submissions of which all authors are students at the time of submission are also eligible for the best student paper award. Papers meeting the requirement for the best student paper award should indicate this during submission.
Besides the best paper and best student paper award, during the IPEC conference, the IPEC Nerode Prize will be conferred. The winner(s) will be chosen by a separate award committee; please refer to the webpage for details.
The 2025 IPEC Programme Committee awarded the 2025 IPEC Best Paper Award to the paper Kernelization for H-Coloring by Yael Berkman and Ishay Haviv. No Best Student paper was awarded this year.
PACE 2025
The Parameterized Algorithms and Computational Experiments Challenge (PACE) was conceived in Fall 2015 to deepen the relationship between parameterized algorithms and practice. Topics from multivariate algorithms, exact algorithms, fine-grained complexity, and related fields are in scope.
This year’s challenge is about the Dominating Set and Hitting Set problems. Dominating Set has many applications e.g. in facility and resource location, coverage problems, and many more. Hitting Set generalizes many problems, such as Vertex Cover, Dominating Set, Feedback Vertex Set, etc. Both problems are among Karp’s classical NP-complete problems but can be well approximated by a simple greedy algorithm. The problems are W[2]-complete in general, but fixed-parameter tractable on many structurally restricted input classes.
For more details on the timeline and past challenges, please visit the PACE website.
Committees
Program Committee
Akanksha Agrawal (IIT Madras, India) (co-chair)
Matthias Bentert (University of Bergen, Norway)
Fedor V. Fomin (University of Bergen, Norway)
Markus Hecher (Computer science Research Institute of Lens, France)
Danny Hermelin (Ben-Gurion University of the Negev, Israel)
Tanmay Inamdar (IIT Jodhpur, India)
Yusuke Kobayashi (Kyoto University, Japan)
Stefan Kratsch (Humboldt-Universität zu Berlin, Germany)
Alexandra Lassota (Eindhoven University of Technology, The Netherlands)
Daniel Lokshtanov (University of California Santa Barbara, USA)
Kitty Meeks (University of Glasgow, UK)
Fabrizio Montecchiani (University of Perugia, Italy)
Eunjin Oh (Pohang University of Science and Technology, South Korea)
Yota Otachi (Nagoya University, Japan)
Michał Pilipczuk (University of Warsaw, Poland)
Manuel Sorge (TU Wien, Austria)
Uéverton Souza (Universidade Federal Fluminense, Brazil)
Erik Jan van Leeuwen (Utrecht University, The Netherlands) (co-chair)
Jie Xue (New York University Shanghai, China)
Anna Zych-Pawlewicz (University of Warsaw, Poland)
Steering Committee
Akanksha Agrawal (2024-27)
Hans Bodlaender (2023-26)
Édouard Bonnet (2023-26)
Łukasz Kowalik (2022-25)
Neeldhara Misra (2022-25)
Paweł Rzążewski (2023-26)
Dimitrios Thilikos (2024-27)
Erik Jan van Leeuwen (2024-27)
Magnus Wahlström (2022-25, chair)