迂回の特性を捉えた最短遷移アルゴリズムに関する研究

• Project/Area Number: 19K11814
• 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: Tohoku University
• Principal Investigator: 伊藤 健洋 東北大学, 情報科学研究科, 教授 (40431548)
• Project Period (FY): 2019-04-01 – 2025-03-31
• Project Status: Granted (Fiscal Year 2023)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2021: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2020: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 組合せ遷移 / グラフアルゴリズム / マッチング

Outline of Research at the Start

組合せ遷移は，持続的システムや組合せパズルといった多くの動的な状況を数理モデル化し，そのアルゴリズムを理論解析する研究である．本研究では「遷移に必要な最小ステップ数はいくつか？」という最短遷移問題に対し，アルゴリズム手法の開発を目指す．特に，異なるタイプの問題を比較検証することで，最短遷移問題の難しさの本質に迫り，開発したアルゴリズムを基礎手法として汎用化することを目指す．

Outline of Annual Research Achievements

本年度は，Kempeら (2002年) が導入した時間ネットワークの概念において，その関連する遷移問題を研究した．この概念は，分散通信などネットワーク上の時間制約を解析するために導入され，時間ラベル付き有向グラフによって表現される．本研究では，時間制約付き有向全域木を対象とした遷移問題を解析した．これまでの研究に依って，時間制約の条件がない場合には，無向グラフであっても有向グラフであっても，任意の2つの全域木は互いに遷移可能であると知られている．すなわち，これら全域木からなる解空間グラフは常に連結である．加えて，無向・有向のいずれのグラフであっても，全域木の最短遷移問題も多項式時間で解けることが知られている．それとは対照的に，本研究では，時間制約を導入した場合には，解空間グラフは非連結となり得ることをまず示した．次に，そのような解空間グラフであっても，与えられた2つの時間制約付き有向全域木が互いに遷移可能であるかどうか（すなわち，到達判定）が，多項式時間で解けることを示した．その一方で，時間制約がある場合には最短遷移問題がNP困難であることを示し，時間制約の有無に依って計算複雑性が変わるという対比を示すことができた．
本年度は他にも，グラフ上のラベル付きトークン遷移問題に関する研究も行った．この問題では多項式長の遷移系列の存在が示せるため，最短遷移問題が研究対象となる．この問題は，量子プログラムのコンパイラ設計に現れる量子ビットルーティング問題として，これまでも研究されてきた．既存研究では実践的なアプローチが主であったが，本研究では計算複雑性の理論的な解析に取り組み，NP困難性や特殊ケースにおける多項式時間アルゴリズム等を開発した．

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

グラフに関する最短遷移問題において，これまでに本研究で開発してきたアルゴリズム手法や計算困難性の解析手法を活用して，時間制約付き有向全域木やラベル付きトークン遷移等の最短遷移問題の解析を進めることができた．また，研究成果の取りまとめも進められており，学術雑誌への論文掲載等へと繋がっている．

Strategy for Future Research Activity

コロナ禍に依る行動制限もなくなったため，海外現地での研究成果の発表を行い，参加者らからのコメントやディスカッション等を得て，本研究の成果をまとめていく予定である．その過程では，本年度のように，新たな（最短）遷移問題への開発手法の活用も試みることで，本研究に依って得られた知見や解析手法を整理していきたい．

Research Products

• [Int'l Joint Research] Universite de Lyon/Universite de Bordeaux/Universite Grenoble Alpes(フランス)
• [Int'l Joint Research] University of Bremen(ドイツ)
• [Int'l Joint Research] ボルドー大学/リヨン第1大学(フランス)
• [Int'l Joint Research] ボルドー大学/リヨン第1大学/グルノーブル・アルプ大学(フランス)
• [Int'l Joint Research] ドルトムント工科大学(ドイツ)
• [Int'l Joint Research] グルノーブル国立工科大学/リヨン第１大学/ボルドー大学(フランス)
• [Int'l Joint Research] ウォータールー大学(カナダ)
• [Int'l Joint Research] ドルトムント工科大学(ドイツ)
• [Journal Article] Reconfiguration of spanning trees with degree constraints or diameter constraints (2023)
  • Author(s): Nicolas Bousquet, Takehiro Ito, Yusuke Kobayashi, Haruka Mizuta, Paul Ouvrard, Akira Suzuki and Kunihiro Wasa
  • Journal Title: Algorithmica Volume: - Issue: 9 Pages: 2779-2816
  • DOI: 10.1007/s00453-023-01117-z
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] ZDD-based algorithmic framework for solving shortest reconfiguration problems (2023)
  • Author(s): Takehiro Ito, Jun Kawahara, Yu Nakahata, Takehide Soh, Akira Suzuki, Junichi Teruyama and Takahisa Toda
  • Journal Title: Proceedings of the 20th International Conference on the Integration of Constraint Programming, Artificial Intelligence, and Operations Research (CPAIOR 2023), Lecture Notes in Computer Science (LNCS) Volume: 13884 Pages: 1-17
  • DOI: 10.1007/978-3-031-33271-5_12
  • ISBN: 9783031332708, 9783031332715
  • Peer Reviewed / Open Access
• [Journal Article] Fixed-parameter algorithms for graph constraint logic (2023)
  • Author(s): Tatsuhiko Hatanaka, Felix Hommelsheim, Takehiro Ito, Yusuke Kobayashi, Moritz Muhlenthaler, Akira Suzuki
  • Journal Title: Theoretical Computer Science Volume: 959 Pages: 113863-113863
  • DOI: 10.1016/j.tcs.2023.113863
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Reconfiguration of colorings in triangulations of the sphere (2023)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Journal Title: Proc. of 39th International Symposium on Computational Geometry (SoCG 2023), Leibniz International Proceedings in Informatics Volume: 258
  • Peer Reviewed / Open Access
• [Journal Article] Reconfiguration of cliques in a graph (2023)
  • Author(s): Ito Takehiro、Ono Hirotaka、Otachi Yota
  • Journal Title: Discrete Applied Mathematics Volume: 333 Pages: 43-58
  • DOI: 10.1016/j.dam.2023.01.026
  • Peer Reviewed
• [Journal Article] Algorithmic theory of qubit routing (2023)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Yoshio Okamoto
  • Journal Title: Proc. of 18th Algorithms and Data Structures Symposium (WADS 2023), Lecture Notes in Computer Science Volume: 14079 Pages: 533-546
  • DOI: 10.1007/978-3-031-38906-1_35
  • ISBN: 9783031389054, 9783031389061
  • Peer Reviewed / Open Access
• [Journal Article] Reconfiguration of Time-Respecting Arborescences (2023)
  • Author(s): Ito Takehiro、Iwamasa Yuni、Kamiyama Naoyuki、Kobayashi Yasuaki、Kobayashi Yusuke、Maezawa Shun-ichi、Suzuki Akira
  • Journal Title: Algorithms and Data Structures (WADS 2023) Volume: 14079 Pages: 521-532
  • DOI: 10.1007/978-3-031-38906-1_34
  • ISBN: 9783031389054, 9783031389061
  • Peer Reviewed / Open Access
• [Journal Article] Hardness of finding combinatorial shortest paths on graph associahedra (2023)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto
  • Journal Title: Proc. of 50th EATCS International Colloquium on Automata, Languages and Programming (ICALP 2023), Leibniz International Proceedings in Informatics Volume: 261
  • Peer Reviewed / Open Access
• [Journal Article] Rerouting planar curves and disjoint paths (2023)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Naonori Kakimura, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Journal Title: Proc. of 50th EATCS International Colloquium on Automata, Languages and Programming (ICALP 2023), Leibniz International Proceedings in Informatics Volume: 261
  • Peer Reviewed / Open Access
• [Journal Article] Sorting balls and water: Equivalence and computational complexity (2023)
  • Author(s): Takehiro Ito, Jun Kawahara, Shin-ichi Minato, Yota Otachi, Toshiki Saitoh, Akira Suzuki, Ryuhei Uehara, Takeaki Uno, Katsuhisa Yamanaka, Ryo Yoshinaka
  • Journal Title: Theoretical Computer Science Volume: 927 Pages: 114158-114158
  • DOI: 10.1016/j.tcs.2023.114158
  • Peer Reviewed / Open Access
• [Journal Article] On reachable assignments under dichotomous preferences (2023)
  • Author(s): Ito Takehiro、Kakimura Naonori、Kamiyama Naoyuki、Kobayashi Yusuke、Nozaki Yuta、Okamoto Yoshio、Ozeki Kenta
  • Journal Title: Theoretical Computer Science Volume: 979 Pages: 114196-114196
  • DOI: 10.1016/j.tcs.2023.114196
  • Peer Reviewed / Open Access
• [Journal Article] Solving reconfiguration problems of first-order expressible properties of graph vertices with Boolean satisfiability (2023)
  • Author(s): Takahisa Toda, Takehiro Ito, Jun Kawahara, Takehide Soh, Akira Suzuki, Junichi Teruyama
  • Journal Title: Proc. of 35th IEEE International Conference on Tools with Artificial Intelligence (ICTAI 2023) Volume: - Pages: 294-302
  • DOI: 10.1109/ictai59109.2023.00050
  • Peer Reviewed / Open Access
• [Journal Article] Reconfiguring (non-spanning) arborescences (2023)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Yasuaki Kobayashi, Yu Nakahata, Yota Otachi, Kunihiro Wasa
  • Journal Title: Theoretical Computer Science Volume: 943 Pages: 131-141
  • DOI: 10.1016/j.tcs.2022.12.007
  • Peer Reviewed / Open Access
• [Journal Article] Monotone edge flips to an orientation of maximum edge-connectivity a la Nash-Williams (2023)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Journal Title: ACM Transactions on Algorithms Volume: 19 Issue: 1 Pages: 6-6
  • DOI: 10.1145/3561302
  • Peer Reviewed / Open Access
• [Journal Article] Reconfiguration of vertex-disjoint shortest paths on graphs (2023)
  • Author(s): Rin Saito, Hiroshi Eto, Takehiro Ito, Ryuhei Uehara
  • Journal Title: Proc. of 17th International Conference and Workshops on Algorithms and Computation (WALCOM 2023), Lecture Notes in Computer Science Volume: 13973 Pages: 191-201
  • DOI: 10.1007/978-3-031-27051-2_17
  • ISBN: 9783031270505, 9783031270512
  • Peer Reviewed
• [Journal Article] Approximability of the Distance Independent Set Problem on Regular Graphs and Planar Graphs (2022)
  • Author(s): Hiroshi Eto, Takehiro Ito, Zhilong Liu, Eiji Miyano
  • Journal Title: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences Volume: E105.A Issue: 9 Pages: 1211-1222
  • DOI: 10.1587/transfun.2021DMP0017
  • ISSN: 0916-8508, 1745-1337
  • Year and Date: 2022-09-01
  • Peer Reviewed
• [Journal Article] Happy set problem on subclasses of co-comparability graphs (2022)
  • Author(s): Hiroshi Eto, Takehiro Ito, Eiji Miyano, Akira Suzuki and Yuma Tamura
  • Journal Title: Algorithmica Volume: - Issue: 11 Pages: 1-21
  • DOI: 10.1007/s00453-022-01081-0
  • Peer Reviewed
• [Journal Article] A parameterized view to the robust recoverable base problem of matroids under structural uncertainty (2022)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Yoshio Okamoto
  • Journal Title: Operations Research Letters Volume: 50 Issue: 3 Pages: 370-375
  • DOI: 10.1016/j.orl.2022.05.001
  • Peer Reviewed / Open Access
• [Journal Article] Shortest reconfiguration of perfect matchings via alternating cycles (2022)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Yoshio Okamoto
  • Journal Title: SIAM Journal on Discrete Mathematics Volume: 36 Issue: 2 Pages: 1102-1123
  • DOI: 10.1137/20m1364370
  • Peer Reviewed
• [Journal Article] Sorting balls and water: equivalence and computational complexity (2022)
  • Author(s): Takehiro Ito, Jun Kawahara, Shin-ichi Minato, Yota Otachi, Toshiki Saitoh, Akira Suzuki, Ryuhei Uehara, Takeaki Uno, Katsuhisa Yamanaka, Ryo Yoshinaka
  • Journal Title: Proc. of 11th International Conference on Fun with Algorithms (FUN 2022), Leibniz International Proceedings in Informatics Volume: 226
  • Peer Reviewed / Open Access
• [Journal Article] Algorithmic meta-theorems for combinatorial reconfiguration revisited (2022)
  • Author(s): Tatsuya Gima, Takehiro Ito, Yasuaki Kobayashi, Yota Otachi
  • Journal Title: Proc. of 30th Annual European Symposium on Algorithms (ESA 2022), Leibniz International Proceedings in Informatics Volume: 244
  • Peer Reviewed
• [Journal Article] On reachable assignments under dichotomous preferences (2022)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Journal Title: Proc. of 24th International Conference on Principles and Practice of Multi-Agent Systems (PRIMA 2022), Lecture Notes in Computer Science Volume: 13753 Pages: 650-658
  • DOI: 10.1007/978-3-031-21203-1_43
  • ISBN: 9783031212024, 9783031212031
  • Peer Reviewed / Open Access
• [Journal Article] Independent set reconfiguration on directed graphs (2022)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Yasuaki Kobayashi, Yu Nakahata, Yota Otachi, Masahiro Takahashi, Kunihiro Wasa
  • Journal Title: Proc. of 47th International Symposium on Mathematical Foundations of Computer Science, Leibniz International Proceedings in Informatics Volume: 241
  • Peer Reviewed
• [Journal Article] Monotone edge flips to an orientation of maximum edge-connectivity ? la Nash-Williams (2022)
  • Author(s): Ito Takehiro、Iwamasa Yuni、Kakimura Naonori、Kamiyama Naoyuki、Kobayashi Yusuke、Maezawa Shun-ichi、Nozaki Yuta、Okamoto Yoshio、Ozeki Kenta
  • Journal Title: Proceedings of the 2022 Annual ACM-SIAM Symposium on Discrete Algorithms (SODA) Volume: なし Pages: 1342-1355
  • DOI: 10.1137/1.9781611977073.56
  • ISBN: 9781611977073
  • Peer Reviewed / Open Access
• [Journal Article] Reconfiguration of spanning trees with degree constraint or diameter constraint (2022)
  • Author(s): Nicolas Bousquet, Takehiro Ito, Yusuke Kobayashi, Haruka Mizuta, Paul Ouvrard, Akira Suzuki, Kunihiro Wasa
  • Journal Title: Proc. of 39th International Symposium on Theoretical Aspects of Computer Science (STACS 2022), Leibniz International Proceedings in Informatics Volume: 219
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Happy set problem on subclasses of co-comparability graphs (2022)
  • Author(s): Hiroshi Eto, Takehiro Ito, Eiji Miyano, Akira Suzuki, Yuma Tamura
  • Journal Title: Proc. of 16th International Conference and Workshops on Algorithms and Computation (WALCOM 2022), Lecture Notes in Computer Science Volume: 13174 Pages: 149-160
  • DOI: 10.1007/978-3-030-96731-4_13
  • ISBN: 9783030967307, 9783030967314
  • Peer Reviewed / Open Access
• [Journal Article] Invitation to combinatorial reconfiguration (2022)
  • Author(s): Takehiro Ito
  • Journal Title: Proc. of 16th International Conference and Workshops on Algorithms and Computation (WALCOM 2022), Lecture Notes in Computer Science Volume: 13174 Pages: 26-31
  • DOI: 10.1007/978-3-030-96731-4_3
  • NAID: 40021497349
  • ISBN: 9783030967307, 9783030967314
• [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] Algorithms for gerrymandering over graphs (2021)
  • Author(s): Ito Takehiro、Kamiyama Naoyuki、Kobayashi Yusuke、Okamoto Yoshio
  • Journal Title: Theoretical Computer Science Volume: 868 Pages: 30-45
  • DOI: 10.1016/j.tcs.2021.03.037
  • Peer Reviewed / Open Access
• [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] Approximability of the Independent Feedback Vertex Set Problem for Bipartite Graphs (2021)
  • Author(s): Yuma Tamura, Takehiro Ito and Xiao Zhou
  • Journal Title: Theoretical Computer Science Volume: 849 Pages: 227-236
  • DOI: 10.1016/j.tcs.2020.10.026
  • Peer Reviewed
• [Journal Article] Complexity of the Multi-Service Center Problem (2020)
  • Author(s): Takehiro Ito, Naonori Kakimura, and Yusuke Kobayashi
  • Journal Title: Theoretical Computer Science Volume: 842 Pages: 18-27
  • DOI: 10.1016/j.tcs.2020.07.021
  • Peer Reviewed
• [Journal Article] Diameter of colorings under Kempe changes (2020)
  • Author(s): Bonamy Marthe、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Muehlenthaler Moritz、Suzuki Akira、Wasa Kunihiro
  • Journal Title: Theoretical Computer Science Volume: 838 Pages: 45-57
  • DOI: 10.1016/j.tcs.2020.05.033
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Minimization and parameterized variants of vertex partition problems on graphs (2020)
  • Author(s): Tamura Yuma、Ito Takehiro、Zhou Xiao
  • Journal Title: Proc. of ISAAC 2020, Leibniz International Proceedings in Informatics Volume: 181
  • Peer Reviewed / Open Access
• [Journal Article] Fixed-parameter algorithms for graph constraint logic (2020)
  • Author(s): Hatanaka Tatsuhiko、Hommelsheim Felix、Ito Takehiro、Kobayashi Yusuke、Muehlenthaler Moritz、Suzuki Akira
  • Journal Title: Proc. of IPEC 2020, Leibniz International Proceedings in Informatics Volume: 180
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Reconfiguration of spanning trees with many or few leaves (2020)
  • Author(s): Bousquet Nicolas、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Ouvrard Paul、Suzuki Akira、Wasa Kunihiro
  • Journal Title: Proc. of ESA 2020, Leibniz International Proceedings in Informatics Volume: 173
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Reconfiguring spanning and induced subgraphs (2020)
  • Author(s): Hanaka Tesshu、Ito Takehiro、Mizuta Haruka、Moore Benjamin、Nishimura Naomi、Subramanya Vijay、Suzuki Akira、Vaidyanathan Krishna
  • Journal Title: Theoretical Computer Science Volume: 806 Pages: 553-566
  • DOI: 10.1016/j.tcs.2019.09.018
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Shortest reconfiguration of colorings under Kempe changes (2020)
  • Author(s): Bonamy Marthe、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Muehlenthaler Moritz、Suzuki Akira、Wasa Kunihiro
  • Journal Title: Proc. of STACS 2020, Leibniz International Proceedings in Informatics Volume: 154
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Approximability of the independent feedback vertex set problem for bipartite graphs (2020)
  • Author(s): Tamura Yuma、Ito Takehiro、Zhou Xiao
  • Journal Title: Proc. of WALCOM 2020, Lecture Notes in Computer Science Volume: 12049 Pages: 286-295
  • DOI: 10.1007/978-3-030-39881-1_24
  • ISBN: 9783030398804, 9783030398811
  • Peer Reviewed
• [Journal Article] Shortest reconfiguration of matchings (2019)
  • Author(s): Bousquet Nicolas、Hatanaka Tatsuhiko、Ito Takehiro、Muehlenthaler Moritz
  • Journal Title: Proc. of WG 2019, Lecture Notes in Computer Science Volume: 11789 Pages: 162-174
  • DOI: 10.1007/978-3-030-30786-8_13
  • ISBN: 9783030307851, 9783030307868
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Diameter of colorings under Kempe changes (2019)
  • Author(s): Bonamy Marthe、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Muehlenthaler Moritz、Suzuki Akira、Wasa Kunihiro
  • Journal Title: Proc. of COCOON 2019, Lecture Notes in Computer Science Volume: 11653 Pages: 52-64
  • DOI: 10.1007/978-3-030-26176-4_5
  • ISBN: 9783030261757, 9783030261764
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Incremental optimization of independent sets under the reconfiguration framework (2019)
  • Author(s): Ito Takehiro、Mizuta Haruka、Nishimura Naomi、Suzuki Akira
  • Journal Title: Proc. of COCOON 2019, Lecture Notes in Computer Science Volume: 11653 Pages: 313-324
  • DOI: 10.1007/978-3-030-26176-4_26
  • ISBN: 9783030261757, 9783030261764
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Reconfiguration of minimum Steiner trees via vertex exchanges (2019)
  • Author(s): Mizuta Haruka、Hatanaka Tatsuhiko、Ito Takehiro、Zhou Xiao
  • Journal Title: Proc. of MFCS 2019, Leibniz International Proceedings in Informatics Volume: 138
  • Peer Reviewed / Open Access
• [Journal Article] The perfect matching reconfiguration problem (2019)
  • Author(s): Bonamy Marthe、Bousquet Nicolas、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mary Arnaud、Muehlenthaler Moritz、Wasa Kunihiro
  • Journal Title: Proc. of MFCS 2019, Leibniz International Proceedings in Informatics Volume: 138
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Shortest reconfiguration of perfect matchings via alternating cycles (2019)
  • Author(s): Ito Takehiro、Kakimura Naonori、Kamiyama Naoyuki、Kobayashi Yusuke、Okamoto Yoshio
  • Journal Title: Proc. of ESA 2019, Leibniz International Proceedings in Informatics Volume: 144
  • Peer Reviewed / Open Access
• [Presentation] ZDD-based algorithmic framework for solving shortest reconfiguration problems (2023)
  • Author(s): Takehiro Ito, Jun Kawahara, Yu Nakahata, Takehide Soh, Akira Suzuki, Junichi Teruyama, Takahisa Toda
  • Organizer: 20th International Conference on the Integration of Constraint Programming, Artificial Intelligence, and Operations Research (CPAIOR 2023)
  • Int'l Joint Research
• [Presentation] Reconfiguration of colorings in triangulations of the sphere (2023)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Organizer: 39th International Symposium on Computational Geometry (SoCG 2023)
  • Int'l Joint Research
• [Presentation] Hardness of finding combinatorial shortest paths on graph associahedra (2023)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto
  • Organizer: 50th EATCS International Colloquium on Automata, Languages and Programming (ICALP 2023)
  • Int'l Joint Research
• [Presentation] Rerouting planar curves and disjoint paths (2023)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Naonori Kakimura, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Organizer: 50th EATCS International Colloquium on Automata, Languages and Programming (ICALP 2023)
  • Int'l Joint Research
• [Presentation] Reconfiguration of time-respecting arborescences (2023)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Naoyuki Kamiyama, Yasuaki Kobayashi, Yusuke Kobayashi, Shun-ichi Maezawa, Akira Suzuki
  • Organizer: 18th Algorithms and Data Structures Symposium (WADS 2023)
  • Int'l Joint Research
• [Presentation] Algorithmic theory of qubit routing (2023)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Yoshio Okamoto
  • Organizer: 18th Algorithms and Data Structures Symposium (WADS 2023)
  • Int'l Joint Research
• [Presentation] Solving reconfiguration problems of first-order expressible properties of graph vertices with Boolean satisfiability (2023)
  • Author(s): Takahisa Toda, Takehiro Ito, Jun Kawahara, Takehide Soh, Akira Suzuki, Junichi Teruyama
  • Organizer: 35th IEEE International Conference on Tools with Artificial Intelligence (ICTAI 2023)
  • Int'l Joint Research
• [Presentation] Reconfiguration of vertex-disjoint shortest paths on graphs (2023)
  • Author(s): Rin Saito, Hiroshi Eto, Takehiro Ito, Ryuhei Uehara
  • Organizer: 17th International Conference and Workshops on Algorithms and Computation (WALCOM 2023)
  • Int'l Joint Research
• [Presentation] Sorting balls and water: equivalence and computational complexity (2022)
  • Author(s): Takehiro Ito, Jun Kawahara, Shin-ichi Minato, Yota Otachi, Toshiki Saitoh, Akira Suzuki, Ryuhei Uehara, Takeaki Uno, Katsuhisa Yamanaka, Ryo Yoshinaka
  • Organizer: 11th International Conference on Fun with Algorithms (FUN 2022)
  • Int'l Joint Research
• [Presentation] Algorithmic meta-theorems for combinatorial reconfiguration revisited (2022)
  • Author(s): Tatsuya Gima, Takehiro Ito, Yasuaki Kobayashi, Yota Otachi
  • Organizer: 30th Annual European Symposium on Algorithms (ESA 2022)
  • Int'l Joint Research
• [Presentation] On reachable assignments under dichotomous preferences (2022)
  • Author(s): Takehiro Ito, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Organizer: 24th International Conference on Principles and Practice of Multi-Agent Systems (PRIMA 2022)
  • Int'l Joint Research
• [Presentation] Independent set reconfiguration on directed graphs (2022)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Yasuaki Kobayashi, Yu Nakahata, Yota Otachi, Masahiro Takahashi, Kunihiro Wasa
  • Organizer: 47th International Symposium on Mathematical Foundations of Computer Science (MFCS2022)
  • Int'l Joint Research
• [Presentation] Monotone edge flips to an orientation of maximum edge-connectivity a la Nash-Williams (2022)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Naonori Kakimura, Naoyuki Kamiyama, Yusuke Kobayashi, Shun-ichi Maezawa, Yuta Nozaki, Yoshio Okamoto, Kenta Ozeki
  • Organizer: Annual ACM-SIAM Symposium on Discrete Algorithms (SODA 2022)
  • Int'l Joint Research
• [Presentation] Reconfiguration of spanning trees with degree constraint or diameter constraint (2022)
  • Author(s): Nicolas Bousquet, Takehiro Ito, Yusuke Kobayashi, Haruka Mizuta, Paul Ouvrard, Akira Suzuki, Kunihiro Wasa
  • Organizer: 39th International Symposium on Theoretical Aspects of Computer Science (STACS 2022)
  • Int'l Joint Research
• [Presentation] Happy set problem on subclasses of co-comparability graphs (2022)
  • Author(s): Hiroshi Eto, Takehiro Ito, Eiji Miyano, Akira Suzuki, Yuma Tamura
  • Organizer: 16th International Conference and Workshops on Algorithms and Computation (WALCOM 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: 16th International Conference and Workshops on Algorithms and Computation (WALCOM 2022)
  • Int'l Joint Research
• [Presentation] Invitation to combinatorial reconfiguration (2022)
  • Author(s): Takehiro Ito
  • Organizer: 16th International Conference and Workshops on Algorithms and Computation (WALCOM 2022)
  • Int'l Joint Research / Invited
• [Presentation] Reconfiguring directed trees in a digraph (2021)
  • Author(s): Takehiro Ito, Yuni Iwamasa, Yasuaki Kobayashi, Yu Nakahata, Yota Otachi, Kunihiro Wasa
  • Organizer: 27th International Computing and Combinatorics Conference (COCOON 2021)
  • Int'l Joint Research
• [Presentation] Minimization and parameterized variants of vertex partition problems on graphs (2020)
  • Author(s): Tamura Yuma、Ito Takehiro、Zhou Xiao
  • Organizer: 31st International Symposium on Algorithms and Computation (ISAAC 2020)
  • Int'l Joint Research
• [Presentation] Fixed-parameter algorithms for graph constraint logic (2020)
  • Author(s): Hatanaka Tatsuhiko、Hommelsheim Felix、Ito Takehiro、Kobayashi Yusuke、Muehlenthaler Moritz、Suzuki Akira
  • Organizer: 15th International Symposium on Parameterized and Exact Computation (IPEC 2020)
  • Int'l Joint Research
• [Presentation] Reconfiguration of spanning trees with many or few leaves (2020)
  • Author(s): Bousquet Nicolas、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Ouvrard Paul、Suzuki Akira、Wasa Kunihiro
  • Organizer: 28th Annual European Symposium on Algorithms (ESA 2020)
  • Int'l Joint Research
• [Presentation] Shortest reconfiguration of colorings under Kempe changes (2020)
  • Author(s): Bonamy Marthe、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Muehlenthaler Moritz、Suzuki Akira、Wasa Kunihiro
  • Organizer: 37th International Symposium on Theoretical Aspects of Computer Science (STACS 2020)
  • Int'l Joint Research
• [Presentation] Approximability of the independent feedback vertex set problem for bipartite graphs (2020)
  • Author(s): Tamura Yuma、Ito Takehiro、Zhou Xiao
  • Organizer: 14th International Conference and Workshop on Algorithms and Computation (WALCOM 2020)
  • Int'l Joint Research
• [Presentation] Shortest reconfiguration of matchings (2019)
  • Author(s): Bousquet Nicolas、Hatanaka Tatsuhiko、Ito Takehiro、Muehlenthaler Moritz
  • Organizer: 45th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2019)
  • Int'l Joint Research
• [Presentation] Diameter of colorings under Kempe changes (2019)
  • Author(s): Bonamy Marthe、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Muehlenthaler Moritz、Suzuki Akira、Wasa Kunihiro
  • Organizer: 25th International Computing and Combinatorics Conference (COCOON 2019)
  • Int'l Joint Research
• [Presentation] Incremental optimization of independent sets under the reconfiguration framework (2019)
  • Author(s): Ito Takehiro、Mizuta Haruka、Nishimura Naomi、Suzuki Akira
  • Organizer: 25th International Computing and Combinatorics Conference (COCOON 2019)
  • Int'l Joint Research
• [Presentation] Reconfiguration of minimum Steiner trees via vertex exchanges (2019)
  • Author(s): Mizuta Haruka、Hatanaka Tatsuhiko、Ito Takehiro、Zhou Xiao
  • Organizer: 44th International Symposium on Mathematical Foundations of Computer Science (MFCS 2019)
  • Int'l Joint Research
• [Presentation] The perfect matching reconfiguration problem (2019)
  • Author(s): Bonamy Marthe、Bousquet Nicolas、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mary Arnaud、Muehlenthaler Moritz、Wasa Kunihiro
  • Organizer: 44th International Symposium on Mathematical Foundations of Computer Science (MFCS 2019)
  • Int'l Joint Research
• [Presentation] Shortest reconfiguration of perfect matchings via alternating cycles (2019)
  • Author(s): Ito Takehiro、Kakimura Naonori、Kamiyama Naoyuki、Kobayashi Yusuke、Okamoto Yoshio
  • Organizer: 27th Annual European Symposium on Algorithms (ESA 2019)
  • Int'l Joint Research