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On the complexity of H-coloring for special oriented trees

Published: 01 March 2018 Publication History

Abstract

For a fixed digraph H, the H-coloring problem is the problem of deciding whether a given input digraph G admits a homomorphism to H. The CSP dichotomy conjecture of Feder and Vardi is equivalent to proving that, for any H, the H-coloring problem is in P or NP-complete. We confirm this dichotomy for a certain class of oriented trees, which we call special trees (generalizing earlier results on special triads and polyads). Moreover, we prove that every tractable special oriented tree has bounded width, i.e., the corresponding H-coloring problem is solvable by local consistency checking. Our proof relies on recent algebraic tools, namely characterization of congruence meet-semidistributivity via pointing operations and absorption theory.

References

[1]
E. Allender, M. Bauland, N. Immerman, H. Schnoor, H. Vollmer, The complexity of satisfiability problems: Refining schaefers theorem, in: Mathematical Foundations of Computer Science 2005: 30th International Symposium, MFCS 2005, Gdansk, Poland, August 29September 2, 2005 Proceedings, 2005, pp. 7182.
[2]
L. Barto, The dichotomy for conservative constraint satisfaction problems revisited, in: Proceedings of the 26th Annual IEEE Symposium on Logic in Computer Science, LICS 2011, IEEE Computer Society, 2011, pp. 21-24.
[3]
L. Barto, J. Bul.n, CSP dichotomy for special polyads, Internat. J. Algebra Comput., 23 (2013) 1151-1174.
[4]
L. Barto, M. Kozik, Constraint satisfaction problems of bounded width, in: 50th Annual IEEE Symposium on Foundations of Computer Science, 2009 FOCS 09, 2009, pp. 595603.
[5]
L. Barto, M. Kozik, Absorbing subalgebras, cyclic terms, and the constraint satisfaction problem, Logical Methods Comput. Sci., 8 (2012) 27.
[6]
L. Barto, M. Kozik, Robust Satisfiability of Constraint Satisfaction Problems, in: Proceedings of the Forty-fourth Annual ACM Symposium on Theory of Computing, STOC 12, ACM, New York, NY, USA, 2012, pp. 931-940.
[7]
L. Barto, M. Kozik, Constraint satisfaction problems solvable by local consistency methods, J. ACM, 61 (2014) 19.
[8]
L. Barto, M. Kozik, Absorption in universal algebra and CSP, in: The Constraint Satisfaction Problem: Complexity and Approximability, 2017, pp. 45-77.
[9]
L. Barto, M. Kozik, M. Marti, T. Niven, CSP dichotomy for special triads, Proc. Amer. Math. Soc., 137 (2009) 2921-2934.
[10]
L. Barto, M. Kozik, T. Niven, The CSP dichotomy holds for digraphs with no sources and no sinks (a positive answer to a conjecture of Bang-Jensen and Hell), SIAM J. Comput., 38 (2008) 1782-1802.
[11]
L. Barto, M. Kozik, .D. Stanovsk, Maltsev conditions, lack of absorption, and solvability, Algebra Univ., 74 (2015) 185-206.
[12]
C. Bergman, Chapman and Hall/CRC, Boca Raton, 2011.
[13]
J. Berman, P. Idziak, .P. Markovi, R. McKenzie, M. Valeriote, R. Willard, Varieties with few subalgebras of powers, Trans. Amer. Math. Soc., 362 (2010) 1445-1473.
[14]
V.G. Bodnaruk, L.A. Kalunin, V.N. Kotov, B.A. Romov, Galois theory for post algebras. i, II. Otdelenie Matematiki, Mekhaniki i Kibernetiki Akademii Nauk Ukrainskoi SSR, Kibernetika, 3 (1969) 1-9.
[15]
A. Bulatov, Tractable conservative constraint satisfaction problems, in: Proceedings of the 18th Annual IEEE Symposium on Logic in Computer Science, LICS 03, IEEE Computer Society, Washington, DC, USA, 2003, pp. 321.
[16]
A. Bulatov, A dichotomy theorem for constraint satisfaction problems on a 3-element set, J. ACM, 53 (2006) 66-120.
[17]
A. Bulatov, P. Jeavons, A. Krokhin, Classifying the complexity of constraints using finite algebras, SIAM J. Comput., 34 (2005) 720-742.
[18]
A. Bulatov, M. Valeriote, Recent results on the algebraic approach to the CSP, in: Complexity of Constraints, 2008, pp. 68-92.
[19]
J. Buln, .D. Deli, M. Jackson, T. Niven, On the reduction of the CSP dichotomy conjecture to digraphs, in: Lecture Notes in Computer Science, vol. 8124, Springer Berlin Heidelberg, 2013, pp. 184-199.
[20]
J. Buln, .D. Deli, M. Jackson, T. Niven, A finer reduction of constraint problems to digraphs, Log. Methods Comput. Sci., 11 (2015).
[21]
T. Feder, Classification of homomorphisms to oriented cycles and of k-partite satisfiability, SIAM J. Discret. Math., 14 (2001) 471-480.
[22]
T. Feder, M.Y. Vardi, The computational structure of monotone monadic SNP and constraint satisfaction: a study through datalog and group theory, SIAM J. Comput., 28 (1999) 57-104.
[23]
D. Geiger, Closed systems of functions and predicates, Pacific J. Math., 27 (1968) 95-100.
[24]
W. Gutjahr, E. Welzl, G. Woeginger, Polynomial graph-colorings, Discrete Appl. Math., 35 (1992) 29-45.
[25]
R. Hggkvist, P. Hell, D.J. Miller, V. Neuman.Lara, On multiplicative graphs and the product conjecture, Combinatorica, 8 (1988) 63-74.
[26]
P. Hell, J. Neetil, Graphs and Homomorphisms, in: Oxford Lecture Series in Mathematics and its Applications, vol. 28, Oxford University Press, Oxford, New York, 2004.
[27]
P. Hell, J. Neetil, X. Zhu, Complexity of tree homomorphisms, Discrete Appl. Math., 70 (1996) 23-36.
[28]
P. Hell, J. Neetil, X. Zhu, Duality and polynomial testing of tree homomorphisms, Trans. Amer. Math. Soc., 348 (1996) 1281-1297.
[29]
P. Hell, J. Neetil, On the complexity of h-coloring, J. Comb. Theory Ser. B, 48 (1990) 92-110.
[30]
P. Idziak, R. Mckenzie, R. Willard, Tractability and learnability arising from algebras with few subpowers, in: LICS07, IEEE Computer Society, 2007, pp. 213-224.
[31]
P. Jeavons, D. Cohen, M. Gyssens, Closure properties of constraints, J. ACM, 44 (1997) 527-548.
[32]
G. Kun, Constraints, MMSNP and expander relational structures, Combinatorica, 33 (2013) 335-347.
[33]
B. Larose, Algebra and the complexity of digraph CSPs: a survey, in: The Constraint Satisfaction Problem: Complexity and Approximability, 2017, pp. 267-285.
[34]
B. Larose, P. Tesson, Universal algebra and hardness results for constraint satisfaction problems, Theoret. Comput. Sci., 410 (2009) 1629-1647.
[35]
B. Larose, L. Zdori, Bounded width problems and algebras, Algebra Univ., 56 (2007) 439-466.
[36]
M. Marti, R. McKenzie, Existence theorems for weakly symmetric operations, Algebra Universalis, 59 (2008) 463-489.
[37]
T.J. Schaefer, The complexity of satisfiability problems, in: Proceedings of the Tenth Annual ACM Symposium on Theory of Computing, STOC78, ACM, New York, NY, USA, 1978, pp. 216-226.

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  • (2022)Graph Modification for Edge-Coloured and Signed Graph Homomorphism Problems: Parameterized and Classical ComplexityAlgorithmica10.1007/s00453-021-00918-484:5(1183-1212)Online publication date: 1-May-2022
  • (2019)Complexity of Conjunctive Regular Path Query HomomorphismsComputing with Foresight and Industry10.1007/978-3-030-22996-2_10(108-119)Online publication date: 15-Jul-2019
  1. On the complexity of H-coloring for special oriented trees

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      Published In

      cover image European Journal of Combinatorics
      European Journal of Combinatorics  Volume 69, Issue C
      March 2018
      184 pages

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      Academic Press Ltd.

      United Kingdom

      Publication History

      Published: 01 March 2018

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      View all
      • (2023)The smallest hard treesConstraints10.1007/s10601-023-09341-828:2(105-137)Online publication date: 1-Jun-2023
      • (2022)Graph Modification for Edge-Coloured and Signed Graph Homomorphism Problems: Parameterized and Classical ComplexityAlgorithmica10.1007/s00453-021-00918-484:5(1183-1212)Online publication date: 1-May-2022
      • (2019)Complexity of Conjunctive Regular Path Query HomomorphismsComputing with Foresight and Industry10.1007/978-3-030-22996-2_10(108-119)Online publication date: 15-Jul-2019

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