GRASP: A Search Algorithm for Propositional Satisfiability


ÐThis paper introduces GRASP (Generic seaRch Algorithm for the Satisfiability Problem), a new search algorithm for Propositional Satisfiability (SAT). GRASP incorporates several search-pruning techniques that proved to be quite powerful on a wide variety of SAT problems. Some of these techniques are specific to SAT, whereas others are similar in spirit to approaches in other fields of Artificial Intelligence. GRASP is premised on the inevitability of conflicts during the search and its most distinguishing feature is the augmentation of basic backtracking search with a powerful conflict analysis procedure. Analyzing conflicts to determine their causes enables GRASP to backtrack nonchronologically to earlier levels in the search tree, potentially pruning large portions of the search space. In addition, by ªrecordingº the causes of conflicts, GRASP can recognize and preempt the occurrence of similar conflicts later on in the search. Finally, straightforward bookkeeping of the causality chains leading up to conflicts allows GRASP to identify assignments that are necessary for a solution to be found. Experimental results obtained from a large number of benchmarks indicate that application of the proposed conflict analysis techniques to SAT algorithms can be extremely effective for a large number of representative classes of SAT instances.

DOI: 10.1109/12.769433

Extracted Key Phrases

1 Figure or Table

Showing 1-10 of 37 references

Freeman, ªImprovements to Propositional Satisfiability Search Algorithms,º PhD dissertation

  • 1995
2 Excerpts

Marques-Silva, ªSearch Algorithms for Satisfiability Problems in Combinational Switching Circuits,º PhD dissertation

  • 1995

ªA Davis-Putnam Based Enumeration Algorithm for Linear Pseudo-Boolean Optimization

  • P Barth
  • 1995
1 Excerpt

Sakallah, ªEfficient and Robust Test Generation-Based Timing Analysis

  • J P Marques-Silva
  • 1994

DIMACS benchmarks available at ftp://Dimacs.- Rutgers.EDU/pub/challenge/sat/benchmarks/cnf. UCSC benchmarks available at ftp://Dimacs

  • D S Johnson
  • 1993
1 Excerpt

Introduction to Digital Logic Design

  • J P Hayes
  • 1993
Citations per Year

1,162 Citations

Semantic Scholar estimates that this publication has received between 1,014 and 1,333 citations based on the available data.

See our FAQ for additional information.