PDA 3SAT Solver

Please see http://www.pda-solver.com for product EULA

This new Pressure Driven Algorithm (PDA) I have developed solves 3SAT problems well within Polynomial Time given that the number of Clauses is at least 7 times the number of inputs.The algorithm has been tested between 100 and 1638400 inputs with the number of Clauses equal to at least 7 x n.

The results graph (main screenshot) shows the solve times compared with a Polynomial Time of n x E1.32 (where n is the number of inputs, and 1.32 is the polynomial time exponent).The solve times of my algorithm are clearly MUCH better than Polynomial time as the number of inputs increases - making solving large 3SAT problem easy & quick.
This C source code can be adapted to your needs & does require some programming knowledge to use successfully.The main control parameters for the solver are few in number and #defined at the top of the file for easy configuration.

The 3SAT problems that this algorithm solves need to be presented to the algorithm in an array expressed in 3 Conjunctive Normal Form (3CNF).The demo application available in the download showcases the algorithm's solving capacity on randomly generated 3SAT problems over the whole range of tested inputs.


3SAT problem Encoding Format

All SAT instances are of conjunctive normal form formula, i.e., the conjunction of clauses,
where each clause is a disjunction of several literals.

Suppose a formula given as

(x7 + ~x1 + ~x6) (x6 + ~x7 + ~x4) (~x3 + ~x8 + x6) (x8 + ~x6 + ~x1) (~x10 + x2 + x8) (x5 + ~x6 + ~x4) (x1 + ~x7 + ~x6) (~x9 + ~x4 + x7) (x4 + ~x5 + ~x10)

In the encoding format, this formula is stated as follows.

# example of "data" array encoding used by PDA alogorithm code:

7, -1, -6,
6, -7, -4,
-3, -8, 6,
8, -6, -1,
-10, 2, 8,
5, -6, -4,
1, -7, -6,
-9, -4, 7,
4, -5, -10