2-sat

2SAT is a restricted version of the boolean satisfiability problem where the number of variables per clause is at most 2. Works both in node.js and in the browser using browserify.

Example

var twoSat = require("2-sat")

//Solve problem:
//
//    (x1 | !x2) & (x3 | x1) & (x3 | x2)
//
console.log(twoSat(3, [[1, -2], [3, 1], [3,2]]))

API

require("2-sat")(numVariables, clauses)

Finds a satisfying assignment for a 2SAT problem written in conjunctive normal form. If no assignment is possible returns false.

• numVariables is the number of variables
• clauses is a list of binary clauses. Variables are indexed in clauses starting at 1 and negative values indicate negation.

Returns A vector of assignments to the variables of the clause. If problem is not satisfiable, returns false

Credits

(c) 2013 Mikola Lysenko. MIT License