Speeding up FPT algorithms with special tree decompositions

• Project/Area Number: 18K11168
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 60010:Theory of informatics-related
• Research Institution: Nagoya University (2019-2021); Kumamoto University (2018)
• Principal Investigator: Otachi Yota 名古屋大学, 情報学研究科, 准教授 (80610196)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: FPTアルゴリズム / 木構造 / 木幅 / 固定パラメータ容易アルゴリズム

Outline of Final Research Achievements

The concept of treewidth is one of the most important techniques in graph algorithm design. Using special tree structures related to treewidth, we investigated parameterized complexity and designed fast fixed-parameter algorithms for several important problems such as Subgraph Isomorphism, Safe Set, Graph Burning, Grundy Coloring, (A, l)-Path Packing, Firefighting, and Independent Set Reconfiguration.

Academic Significance and Societal Importance of the Research Achievements

特殊木構造を用いて多くの重要問題のより詳細な計算量を知りたいというのがこの研究課題の動機であったが，結果として種々の問題に対する成果を得ることができ，この手法の有用性を示すことができた．
従来の手法では木幅と呼ばれる一般性の高い概念を使って問題を解決することが多かったが，それが難しい場合に対しても本課題で扱った特殊木構造を用いれば高速アルゴリズム設計が可能になる場合が分かった．これは，効率的に解ける問題の範囲を広げより詳しくとらえるために重要なステップであり，今後もこの方向での研究を進める必要がある．

Research Products

• [Int'l Joint Research] Universite Paris Dauphine(フランス)
• [Int'l Joint Research] Utrecht University(オランダ)
• [Int'l Joint Research] Universite Paris Dauphine(フランス)
• [Int'l Joint Research] Universite Paris Dauphine(フランス)
• [Int'l Joint Research] IIT Gandhinagar(インド)
• [Int'l Joint Research] TU Kaiserslautern(ドイツ)
• [Journal Article] Reconfiguration of Regular Induced Subgraphs (2022)
  • Author(s): Eto Hiroshi、Ito Takehiro、Kobayashi Yasuaki、Otachi Yota、Wasa Kunihiro
  • Journal Title: Lecture Notes in Computer Science Volume: 13174 Pages: 35-46
  • DOI: 10.1007/978-3-030-96731-4_4
  • ISBN: 9783030967307, 9783030967314
  • Peer Reviewed
• [Journal Article] Longest common subsequence in sublinear space (2021)
  • Author(s): Kiyomi Masashi、Horiyama Takashi、Otachi Yota
  • Journal Title: Information Processing Letters Volume: 168 Pages: 106084-106084
  • DOI: 10.1016/j.ipl.2020.106084
  • Peer Reviewed
• [Journal Article] Low-congestion shortcut and graph parameters (2021)
  • Author(s): Kitamura Naoki、Kitagawa Hirotaka、Otachi Yota、Izumi Taisuke
  • Journal Title: Distributed Computing Volume: 34 Issue: 5 Pages: 349-365
  • DOI: 10.1007/s00446-021-00401-x
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] On the security number of the Cartesian product of graphs (2021)
  • Author(s): Jakovac Marko、Otachi Yota
  • Journal Title: Discrete Applied Mathematics Volume: 304 Pages: 119-128
  • DOI: 10.1016/j.dam.2021.07.030
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Exploring the Gap Between Treedepth and Vertex Cover Through Vertex?Integrity (2021)
  • Author(s): Gima Tatsuya、Hanaka Tesshu、Kiyomi Masashi、Kobayashi Yasuaki、Otachi Yota
  • Journal Title: Lecture Notes in Computer Science Volume: 12701 Pages: 271-285
  • DOI: 10.1007/978-3-030-75242-2_19
  • ISBN: 9783030752415, 9783030752422
  • Peer Reviewed
• [Journal Article] Computational Complexity of Jumping Block Puzzles (2021)
  • Author(s): Kanzaki Masaaki、Otachi Yota、Uehara Ryuhei
  • Journal Title: Lecture Notes in Computer Science Volume: 13025 Pages: 655-667
  • DOI: 10.1007/978-3-030-89543-3_54
  • ISBN: 9783030895426, 9783030895433
  • Peer Reviewed
• [Journal Article] Reconfiguring Directed Trees in a Digraph (2021)
  • Author(s): Ito Takehiro、Iwamasa Yuni、Kobayashi Yasuaki、Nakahata Yu、Otachi Yota、Wasa Kunihiro
  • Journal Title: Lecture Notes in Computer Science Volume: 13025 Pages: 343-354
  • DOI: 10.1007/978-3-030-89543-3_29
  • ISBN: 9783030895426, 9783030895433
  • Peer Reviewed
• [Journal Article] Distributed Reconfiguration of Spanning Trees (2021)
  • Author(s): Yamauchi Yukiko、Kamiyama Naoyuki、Otachi Yota
  • Journal Title: Lecture Notes in Computer Science Volume: 13046 Pages: 516-520
  • DOI: 10.1007/978-3-030-91081-5_40
  • ISBN: 9783030910808, 9783030910815
  • Peer Reviewed
• [Journal Article] Token Sliding on Split Graphs (2020)
  • Author(s): Belmonte Remy、Kim Eun Jung、Lampis Michael、Mitsou Valia、Otachi Yota、Sikora Florian
  • Journal Title: Theory of Computing Systems Volume: Online Issue: 4 Pages: 662-686
  • DOI: 10.1007/s00224-020-09967-8
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] <i>K</i>₃ Edge Cover Problem in a Wide Sense (2020)
  • Author(s): Chiba Kyohei、Belmonte Remy、Ito Hiro、Lampis Michael、Nagao Atsuki、Otachi Yota
  • Journal Title: Journal of Information Processing Volume: 28 Issue: 0 Pages: 849-858
  • DOI: 10.2197/ipsjjip.28.849
  • NAID: 130007956350
  • ISSN: 1882-6652
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Subgraph Isomorphism on Graph Classes that Exclude a Substructure (2020)
  • Author(s): Bodlaender Hans L.、Hanaka Tesshu、Kobayashi Yasuaki、Kobayashi Yusuke、Okamoto Yoshio、Otachi Yota、van der Zanden Tom C.
  • Journal Title: Algorithmica Volume: 82 Issue: 12 Pages: 3566-3587
  • DOI: 10.1007/s00453-020-00737-z
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Symmetric assembly puzzles are hard, beyond a few pieces (2020)
  • Author(s): Demaine Erik D.、Korman Matias、Ku Jason S.、Mitchell Joseph S.B.、Otachi Yota、van Renssen Andr?、Roeloffzen Marcel、Uehara Ryuhei、Uno Yushi
  • Journal Title: Computational Geometry Volume: 90 Pages: 101648-101648
  • DOI: 10.1016/j.comgeo.2020.101648
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Independent Set Reconfguration Parameterized by Modular-Width (2020)
  • Author(s): Remy Belmonte, Tesshu Hanaka, Michael Lampis, Hirotaka Ono, Yota Otachi
  • Journal Title: Algorithmica Volume: - Issue: 9 Pages: 2586-2605
  • DOI: 10.1007/s00453-020-00700-y
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Parameterized Orientable Deletion (2020)
  • Author(s): Tesshu Hanaka, Ioannis Katsikarelis, Michael Lampis, Yota Otachi, Florian Sikora
  • Journal Title: Algorithmica Volume: - Issue: 7 Pages: 1909-1938
  • DOI: 10.1007/s00453-020-00679-6
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Efficient enumeration of maximal k-degenerate induced subgraphs of a chordal graph (2020)
  • Author(s): Alessio Conte, Mamadou Moustapha Kante, Yota Otachi, Takeaki Uno, Kunihiro Wasa
  • Journal Title: Theoretical Computer Science Volume: 818 Pages: 2-11
  • DOI: 10.1016/j.tcs.2018.08.009
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Parameterized Complexity of Safe Set (2020)
  • Author(s): Belmonte Remy、Hanaka Tesshu、Katsikarelis Ioannis、Lampis Michael、Ono Hirotaka、Otachi Yota
  • Journal Title: Journal of Graph Algorithms and Applications Volume: 24 Issue: 3 Pages: 215-245
  • DOI: 10.7155/jgaa.00528
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Parameterized complexity of graph burning (2020)
  • Author(s): Yasuaki Kobayashi, Yota Otachi
  • Journal Title: Leibniz International Proceedings in Informatics Volume: 180
  • Peer Reviewed / Open Access
• [Journal Article] Grundy distinguishes treewidth from pathwidth (2020)
  • Author(s): Remy Belmonte, Eun Jung Kim, Michael Lampis, Valia Mitsou, Yota Otachi
  • Journal Title: Leibniz International Proceedings in Informatics Volume: 173
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Sublinear-space lexicographic depth-first search for bounded treewidth graphs and planar graphs (2020)
  • Author(s): Taisuke Izumi, Yota Otachi
  • Journal Title: Leibniz International Proceedings in Informatics Volume: 168
  • Peer Reviewed / Open Access
• [Journal Article] Linear-Time Recognition of Double-Threshold Graphs (2020)
  • Author(s): Yusuke Kobayashi, Yoshio Okamoto, Yota Otachi, Yushi Uno
  • Journal Title: Lecture Notes in Computer Science Volume: 12301 Pages: 286-297
  • DOI: 10.1007/978-3-030-60440-0_23
  • ISBN: 9783030604394, 9783030604400
  • Peer Reviewed
• [Journal Article] Parameterized Complexity of (A,l)-Path Packing (2020)
  • Author(s): Belmonte Remy、Hanaka Tesshu、Kanzaki Masaaki、Kiyomi Masashi、Kobayashi Yasuaki、Kobayashi Yusuke、Lampis Michael、Ono Hirotaka、Otachi Yota
  • Journal Title: Lecture Notes in Computer Science Volume: 12126 Pages: 43-55
  • DOI: 10.1007/978-3-030-48966-3_4
  • ISBN: 9783030489656, 9783030489663
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] On Computational Complexity of Pipe Puzzles (2019)
  • Author(s): SHIRAYAMA Takumu、SHIGEMURA Takuto、OTACHI Yota、MIYAZAKI Shuichi、UEHARA Ryuhei
  • Journal Title: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences Volume: E102.A Issue: 9 Pages: 1134-1141
  • DOI: 10.1587/transfun.E102.A.1134
  • NAID: 130007699569
  • ISSN: 0916-8508, 1745-1337
  • Year and Date: 2019-09-01
  • Peer Reviewed
• [Journal Article] Independent Set Reconfiguration Parameterized by Modular-Width (2019)
  • Author(s): Belmonte Remy、Hanaka Tesshu、Lampis Michael、Ono Hirotaka、Otachi Yota
  • Journal Title: Lecture Notes in Computer Science Volume: 11789 Pages: 285-297
  • DOI: 10.1007/978-3-030-30786-8_22
  • ISBN: 9783030307851, 9783030307868
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Low-congestion shortcut and graph parameters (2019)
  • Author(s): Naoki Kitamura, Hirotaka Kitagawa, Yota Otachi, Taisuke Izumi
  • Journal Title: Leibniz International Proceedings in Informatics Volume: 146
  • Peer Reviewed / Open Access
• [Journal Article] A lower bound on opaque sets (2019)
  • Author(s): Kawamura Akitoshi、Moriyama Sonoko、Otachi Yota、Pach J?nos
  • Journal Title: Computational Geometry Volume: 80 Pages: 13-22
  • DOI: 10.1016/j.comgeo.2019.01.002
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] How Bad is the Freedom to Flood-It? (2019)
  • Author(s): Belmonte Remy、Khosravian Ghadikolaei Mehdi、Kiyomi Masashi、Lampis Michael、Otachi Yota
  • Journal Title: Journal of Graph Algorithms and Applications Volume: 23 Issue: 2 Pages: 111-134
  • DOI: 10.7155/jgaa.00486
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Reconfiguration of colorable sets in classes of perfect graphs (2019)
  • Author(s): Ito Takehiro、Otachi Yota
  • Journal Title: Theoretical Computer Science Volume: 772 Pages: 111-122
  • DOI: 10.1016/j.tcs.2018.11.024
  • Peer Reviewed
• [Journal Article] Space-Efficient Algorithms for Longest Increasing Subsequence (2019)
  • Author(s): Kiyomi Masashi、Ono Hirotaka、Otachi Yota、Schweitzer Pascal、Tarui Jun
  • Journal Title: Theory of Computing Systems Volume: - Issue: 3 Pages: 522-541
  • DOI: 10.1007/s00224-018-09908-6
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] On structural parameterizations of firefighting (2019)
  • Author(s): Das Bireswar、Enduri Murali Krishna、Kiyomi Masashi、Misra Neeldhara、Otachi Yota、Reddy I. Vinod、Yoshimura Shunya
  • Journal Title: Theoretical Computer Science Volume: - Pages: 79-90
  • DOI: 10.1016/j.tcs.2019.02.032
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Token sliding on split graphs (2019)
  • Author(s): Remy Belmonte, Eun Jung Kim, Michael Lampis, Valia Mitsou, Yota Otachi, Florian Sikora
  • Journal Title: Leibniz International Proceedings in Informatics Volume: 126
  • DOI: 10.4230/LIPICS.STACS.2019.13
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Parameterized Orientable Deletion (2018)
  • Author(s): Tesshu Hanaka, Ioannis Katsikarelis, Michael Lampis, Yota Otachi, Florian Sikora
  • Journal Title: Leibniz International Proceedings in Informatics Volume: 101
  • DOI: 10.4230/LIPIcs.SWAT.2018.24
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Reconfiguration of colorable sets in classes of perfect graphs (2018)
  • Author(s): Takehiro Ito, Yota Otachi
  • Journal Title: Leibniz International Proceedings in Informatics Volume: 101
  • DOI: 10.4230/LIPIcs.SWAT.2018.27
  • Peer Reviewed / Open Access
• [Journal Article] Computational Complexity of Robot Arm Simulation Problems (2018)
  • Author(s): Feng Tianfeng、Horiyama Takashi、Okamoto Yoshio、Otachi Yota、Saitoh Toshiki、Uno Takeaki、Uehara Ryuhei
  • Journal Title: Lecture Notes in Computer Science Volume: 10979 Pages: 177-188
  • DOI: 10.1007/978-3-319-94667-2_15
  • ISBN: 9783319946665, 9783319946672
  • Peer Reviewed
• [Presentation] Computing diverse shortest paths efficiently: A theoretical and experimental study (2022)
  • Author(s): Tesshu Hanaka, Yasuaki Kobayashi, Kazuhiro Kurita, See Woo Lee, Yota Otachi
  • Organizer: The 36th AAAI Conference on Artificial Intelligence (AAAI 2022)
  • Int'l Joint Research
• [Presentation] Reconfiguration of regular induced subgraphs (2022)
  • Author(s): Hiroshi Eto, Takehiro Ito, Yasuaki Kobayashi, Yota Otachi, Kunihiro Wasa
  • Organizer: The 16th International Conference and Workshops on Algorithms and Computation (WALCOM 2022)
  • Int'l Joint Research
• [Presentation] Exploring the gap between treedepth and vertex cover through vertex integrity (2021)
  • Author(s): Tatsuya Gima, Tesshu Hanaka, Masashi Kiyomi, Yasuaki Kobayashi, Yota Otachi
  • Organizer: The 12th International Conference on Algorithms and Complexity (CIAC 2021)
  • Int'l Joint Research
• [Presentation] Computational complexity of jumping block puzzles (2021)
  • Author(s): Masaaki Kanzaki, Yota Otachi, Ryuhei Uehara
  • Organizer: The 27th International Computing and Combinatorics Conference (COCOON 2021)
  • Int'l Joint Research
• [Presentation] Reconfiguring directed trees in a digraph (2021)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Yasuaki Kobayashi, Yu Nakahata, Yota Otachi, Kunihiro Wasa
  • Organizer: The 27th International Computing and Combinatorics Conference (COCOON 2021)
  • Int'l Joint Research
• [Presentation] Distributed reconfiguration of spanning trees (2021)
  • Author(s): Yukiko Yamauchi, Naoyuki Kamiyama, Yota Otachi
  • Organizer: The 23rd International Symposium on Stabilization, Safety, and Security of Distributed Systems (SSS 2021)
  • Int'l Joint Research
• [Presentation] Finding diverse trees, paths, and more (2021)
  • Author(s): Tesshu Hanaka, Yasuaki Kobayashi, Kazuhiro Kurita, Yota Otachi
  • Organizer: The 35th AAAI Conference on Artificial Intelligence (AAAI 2021)
  • Int'l Joint Research
• [Presentation] Parameterized complexity of graph burning (2020)
  • Author(s): Yasuaki Kobayashi, Yota Otachi
  • Organizer: The 15th International Symposium on Parameterized and Exact Computation (IPEC 2020)
  • Int'l Joint Research
• [Presentation] Grundy distinguishes treewidth from pathwidth (2020)
  • Author(s): Remy Belmonte, Eun Jung Kim, Michael Lampis, Valia Mitsou, Yota Otachi
  • Organizer: The 28th European Symposium on Algorithms (ESA 2020)
  • Int'l Joint Research
• [Presentation] Sublinear-space lexicographic depth-first search for bounded treewidth graphs and planar graphs (2020)
  • Author(s): Taisuke Izumi, Yota Otachi
  • Organizer: The 47th International Colloquium on Automata, Languages and Programming (ICALP 2020)
  • Int'l Joint Research
• [Presentation] Linear-time recognition of double-threshold graphs (2020)
  • Author(s): Yusuke Kobayashi, Yoshio Okamoto, Yota Otachi, Yushi Uno
  • Organizer: The 46th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2020)
  • Int'l Joint Research
• [Presentation] Parameterized complexity of (A, l)-path packing (2020)
  • Author(s): Remy Belmonte, Tesshu Hanaka, Masaaki Kanzaki, Masashi Kiyomi, Yasuaki Kobayashi, Yusuke Kobayashi, Michael Lampis, Hirotaka Ono, Yota Otachi
  • Organizer: The 31st International Workshop on Combinatorial Algorithms (IWOCA 2020)
  • Int'l Joint Research
• [Presentation] Hedonic seat arrangement problems (Extended abstract) (2020)
  • Author(s): Hans L. Bodlaender, Tesshu Hanaka, Lars Jaffke, Hirotaka Ono, Yota Otachi, Tom C. van der Zanden
  • Organizer: The 19th International Conference on Autonomous Agents and Multi-Agent Systems (AAMAS 2020)
  • Int'l Joint Research
• [Presentation] Parameterized complexity of safe set (2019)
  • Author(s): Remy Belmonte, Tesshu Hanaka, Ioannis Katsikarelis, Michael Lampis, Hirotaka Ono, Yota Otachi.
  • Organizer: The 11th International Conference on Algorithms and Complexity (CIAC 2019).
  • Int'l Joint Research
• [Presentation] Subgraph isomorphism on graph classes that exclude a substructure. (2019)
  • Author(s): Hans L. Bodlaender, Tesshu Hanaka, Yoshio Okamoto, Yota Otachi, Tom van der Zanden.
  • Organizer: The 11th International Conference on Algorithms and Complexity (CIAC 2019).
  • Int'l Joint Research
• [Presentation] Independent set reconfiguration parameterized by modular-width (2019)
  • Author(s): Remy Belmonte, Tesshu Hanaka, Michael Lampis, Hirotaka Ono, Yota Otachi.
  • Organizer: The 45th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2019).
  • Int'l Joint Research
• [Presentation] Low-congestion shortcut and graph parameters (2019)
  • Author(s): Naoki Kitamura, Hirotaka Kitagawa, Yota Otachi, Taisuke Izumi.
  • Organizer: The 33rd International Symposium on Distributed Computing (DISC 2019).
  • Int'l Joint Research
• [Presentation] Token sliding on split graphs (2019)
  • Author(s): Remy Belmonte, Eun Jung Kim, Michael Lampis, Valia Mitsou, Yota Otachi, Florian Sikora
  • Organizer: The 36th International Symposium on Theoretical Aspects of Computer Science (STACS 2019)
  • Int'l Joint Research
• [Presentation] Parameterized Orientable Deletion (2018)
  • Author(s): Tesshu Hanaka, Ioannis Katsikarelis, Michael Lampis, Yota Otachi, Florian Sikora
  • Organizer: The 16th Scandinavian Symposium and Workshops on Algorithm Theory (SWAT 2018)
  • Int'l Joint Research
• [Presentation] Reconfiguration of colorable sets in classes of perfect graphs (2018)
  • Author(s): Takehiro Ito, Yota Otachi
  • Organizer: The 16th Scandinavian Symposium and Workshops on Algorithm Theory (SWAT 2018)
  • Int'l Joint Research
• [Presentation] Computational complexity of robot arm simulation problems (2018)
  • Author(s): Tianfeng Feng, Takashi Horiyama, Yoshio Okamoto, Yota Otachi, Toshiki Saitoh, Takeaki Uno, Ryuhei Uehara
  • Organizer: The 29th International Workshop on Combinational Algorithms (IWOCA 2018)
  • Int'l Joint Research
• [Remarks] Yota Otachi @ Nagoya University
  • URL: https://www.math.mi.i.nagoya-u.ac.jp/~otachi/
• [Remarks] Yota Otachi @ Kumamoto University
  • URL: http://www.cs.kumamoto-u.ac.jp/~otachi/