picosat-0.1.2: Bindings to the PicoSAT solver

Safe HaskellNone



We wish to find a solution that satisifes the following logical condition.

 (A v ¬B v C) ∧ (B v D v E) ∧ (D v F)

We can specify this as a zero-terminated lists of integers, with integers mapping onto the variable as ordered in the condition and with integer negation corresponding to logical negation of the specific clause.

 1 -2 3 0
 2 4 5 0
 4 6 0

We feed this list of clauses to the SAT solver using the solve function.

import Picosat

main :: IO [Int]
main = do
  solve [[1, -2, 3], [2,4,5], [4,6]]
  -- Solution [1,-2,3,4,5,6]

The solution given we can interpret as:

  1  A
 -2 ~B
  3  C
  4  D
  5  E
  6  F

To generate all satisfiable solutions, use solveAll function.:

import Picosat

main :: IO [Int]
main = solveAll [[1,2]]
  -- [Solution [1,2],Solution [-1,2],Solution [1,-2]]

For a higher level interface see: http://hackage.haskell.org/package/picologic



solve :: [[Int]] -> IO SolutionSource

Solve a list of CNF constraints yielding the first solution.

solveAll :: [[Int]] -> IO [Solution]Source

Solve a list of CNF constraints yielding all possible solutions.