Modern SAT solvers: fast, neat and underused (2018)

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  • scala

    Scala 2 compiler and standard library. Bugs at; Scala 3 at

    Compiling Scala without a SAT solver is probably too difficult.

    The CNF Converter is a gem.

  • sturm

    Simpleminded terminal interface

    FWIW, here's a little console-mode puzzle game of SAT problems, if you want to solve some manually. The "board" is not exactly like the example table in the post, since that one was for Sudoku in particular. This grid represents variables as rows and clauses as columns. (Python 2)

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  • clingo

    🤔 A grounder and solver for logic programs.

    Love this article and the push to build awareness of what modern SAT solvers can do.

    The thing it misses, though, is that there are higher level abstractions that are far more accessible than SAT. If I were teaching a course on this, I would start with either Answer Set Programming or Satisfiability Modulo Theories (SMT). The most widely used solvers for those are clingo [0] and Z3 [1]:

    With ASP, you write in a much clearer Prolog-like syntax that does not require nearly as much encoding effort as your typical SAT problem. Z3 is similar -- you can code up problems in a simple Python API, or write them in the smtlib language.

    Both of these make it easy to add various types of optimization, constraints, etc. to your problem, and they're much better as modeling languages than straight SAT. Underneath, they have solvers that leverage all the modern CDCL tricks.

    We wrote up a paper [2] on how to formulate a modern dependency solver in ASP; it's helped tremendously for adding new types of features like options, variants, and complex compiler/arch dependencies to Spack [3]. You could not get good solutions to some of these problems without a capable and expressive solver.


  • z3

    The Z3 Theorem Prover

  • spack

    A flexible package manager that supports multiple versions, configurations, platforms, and compilers.

  • pub

    The package manager for Dart

  • Decider

    An Open Source .Net Constraint Programming Solver (by lifebeyondfife)

    Plug for my Constraint Solver if anyone wants a simple example

  • Sonar

    Write Clean Python Code. Always.. Sonar helps you commit clean code every time. With over 225 unique rules to find Python bugs, code smells & vulnerabilities, Sonar finds the issues while you focus on the work.

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