Skip to main content

Exact Algorithms for Maximum Two-Satisfiability

  • Reference work entry
  • First Online:
Encyclopedia of Algorithms
  • 73 Accesses

Years and Authors of Summarized Original Work

  • 2004; Williams

Problem Definition

In the maximum 2-satisfiability problem (abbreviated as Max 2-Sat), one is given a Boolean formula in conjunctive normal form, such that each clause contains at most two literals. The task is to find an assignment to the variables of the formula such that a maximum number of clauses are satisfied.

Max 2-Sat is a classic optimization problem. Its decision version was proved NP-complete by Garey, Johnson, and Stockmeyer [7], in stark contrast with 2-Sat which is solvable in linear time [2]. To get a feeling for the difficulty of the problem, the NP-completeness reduction is sketched here. One can transform any 3-Sat instance F into a Max 2-Sat instance F′, by replacing each clause of F such as

$$\displaystyle\begin{array}{rcl} c_{i} = (\ell_{1} \vee \ell_{2} \vee \ell_{3}),& & {}\\ \end{array}$$

where â„“1, â„“2, and â„“3 are arbitrary literals, with the collection of 2-CNF clauses

$$\displaystyle\begin{array}{rcl}...

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 1,599.99
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Hardcover Book
USD 1,999.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Recommended Reading

  1. Alon N, Galil Z, Margalit O (1997) On the exponent of the all-pairs shortest path problem. J Comput Syst Sci 54:255–262

    Article  MathSciNet  MATH  Google Scholar 

  2. Aspvall B, Plass MF, Tarjan RE (1979) A linear-time algorithm for testing the truth of certain quantified boolean formulas. Inf Proc Lett 8(3):121–123

    Article  MathSciNet  MATH  Google Scholar 

  3. Bansal N, Raman V (1999) Upper bounds for Max Sat: further improved. In: Proceedings of ISAAC, Chennai. LNCS, vol 1741. Springer, Berlin, pp 247–258

    Google Scholar 

  4. Coppersmith D, Winograd S (1990) Matrix multiplication via arithmetic progressions. JSC 9(3):251–280

    MathSciNet  MATH  Google Scholar 

  5. Dantsin E, Wolpert A (2006) Max SAT for formulas with constant clause density can be solved faster than in O(2n) time. In: Proceedings of the 9th international conference on theory and applications of satisfiability testing, Seattle. LNCS, vol 4121. Springer, Berlin, pp 266–276

    Google Scholar 

  6. Dorn F (2006) Dynamic programming and fast matrix multiplication. In: Proceedings of 14th annual European symposium on algorithms, Zurich. LNCS, vol 4168. Springer, Berlin, pp 280–291

    Google Scholar 

  7. Garey M, Johnson D, Stockmeyer L (1976) Some simplified NP-complete graph problems. Theor Comput Sci 1:237–267

    Article  MathSciNet  MATH  Google Scholar 

  8. Gramm J, Niedermeier R (2000) Faster exact solutions for Max2Sat. In: Proceedings of CIAC. LNCS, vol 1767, Rome. Springer, Berlin, pp 174–186

    Google Scholar 

  9. Hirsch EA (2000) A 2m∕4-time algorithm for Max 2-SAT: corrected version. Electronic colloquium on computational complexity report TR99-036

    Google Scholar 

  10. Itai A, Rodeh M (1978) Finding a minimum circuit in a graph. SIAM J Comput 7(4):413–423

    Article  MathSciNet  MATH  Google Scholar 

  11. Kneis J, Mölle D, Richter S, Rossmanith P (2005) Algorithms based on the treewidth of sparse graphs. In: Proceedings of workshop on graph theoretic concepts in computer science, Metz. LNCS, vol 3787. Springer, Berlin, pp 385–396

    Google Scholar 

  12. Kojevnikov A, Kulikov AS (2006) A new approach to proving upper bounds for Max 2-SAT. In: Proceedings of the seventeenth annual ACM-SIAM symposium on discrete algorithms, Miami, pp 11–17

    MATH  Google Scholar 

  13. Mahajan M, Raman V (1999) Parameterizing above guaranteed values: MAXSAT and MAXCUT. J Algorithms 31(2):335–354

    Article  MathSciNet  MATH  Google Scholar 

  14. Niedermeier R, Rossmanith P (2000) New upper bounds for maximum satisfiability. J Algorithms 26:63–88

    Article  MathSciNet  MATH  Google Scholar 

  15. Scott A, Sorkin G (2003) Faster algorithms for MAX CUT and MAX CSP, with polynomial expected time for sparse instances. In: Proceedings of RANDOM-APPROX 2003, Princeton. LNCS, vol 2764. Springer, Berlin, pp 382–395

    Google Scholar 

  16. Vassilevska Williams V (2012) Multiplying matrices faster than Coppersmith-Winograd. In: Proceedings of the 44th annual ACM symposium on theory of computing, New York, pp 887–898

    Google Scholar 

  17. Williams R (2004) On computing k-CNF formula properties. In: Theory and applications of satisfiability testing. LNCS, vol 2919. Springer, Berlin, pp 330–340

    Google Scholar 

  18. Williams R (2005) A new algorithm for optimal 2-constraint satisfaction and its implications. Theor Comput Sci 348(2–3):357–365

    Article  MathSciNet  MATH  Google Scholar 

  19. Williams R (2007) Algorithms and resource requirements for fundamental problems. PhD thesis, Carnegie Mellon University

    Google Scholar 

  20. Woeginger GJ (2003) Exact algorithms for NP-hard problems: a survey. In: Combinatorial optimization – Eureka! You shrink! LNCS, vol 2570. Springer, Berlin, pp 185–207

    Chapter  Google Scholar 

  21. Woeginger GJ (2004) Space and time complexity of exact algorithms: some open problems. In: Proceedings of 1st international workshop on parameterized and exact computation (IWPEC 2004), Bergen. LNCS, vol 3162. Springer, Berlin, pp 281–290

    Google Scholar 

  22. Yuval G (1976) An algorithm for finding all shortest paths using N2. 81 infinite-precision multiplications. Inf Process Lett 4(6):155–156

    Article  MathSciNet  MATH  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Ryan Williams .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2016 Springer Science+Business Media New York

About this entry

Cite this entry

Williams, R. (2016). Exact Algorithms for Maximum Two-Satisfiability. In: Kao, MY. (eds) Encyclopedia of Algorithms. Springer, New York, NY. https://doi.org/10.1007/978-1-4939-2864-4_227

Download citation

Publish with us

Policies and ethics