SATISFIABILITY_MPI is a C++ program which demonstrates, for a particular circuit, an exhaustive search for solutions of the circuit satisfiability problem. This version of the program uses MPI to carry out the solution in parallel.
This problem assumes that we are given a logical circuit of AND, OR and NOT gates, with N binary inputs and a single output. We are to determine all inputs which produce a 1 as the output.
The general problem is NP complete, so there is no known polynomial-time algorithm to solve the general case. The natural way to search for solutions then is exhaustive search.
In an interesting way, this is a very extreme and discrete version of the problem of maximizing a scalar function of multiple variables. The difference is that here we know that both the input and output only have the values 0 and 1, rather than a continuous range of real values!
This problem was a natural candidate for parallel computation, since the individual evaluations of the circuit are completely independent.
The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.
CNF is data directory which describes the DIMACS CNF file format for defining instances of the satisfiability problem in for boolean formulas in conjunctive normal form.
COMBO is a FORTRAN90 library which includes many combinatorial routines.
HEAT_MPI is a C++ program which solves the 1D Time Dependent Heat Equation using MPI.
LAU_NP is a FORTRAN90 library which implements heuristic algorithms for various NP-hard combinatorial problems.
MPI is a directory of C++ examples which illustrate the use of the MPI application program interface for carrying out parallel computatioins in a distributed memory environment.
QUAD_MPI is a C++ program which approximates an integral using a quadrature rule, and carries out the computation in parallel using MPI.
RANDOM_MPI, a C++ program which demonstrates one way to generate the same sequence of random numbers for both sequential execution and parallel execution under MPI.
SATISFIABILITY is a C++ program which solves the circuit satisfiability problem.
SATISFIABILITY_MPI is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version.
SATISFIABILITY_OPEN_MP is a C++ program which solves the circuit satisfiability problem using the OpenMP parallel programming system.
SUBSET is a C++ library which enumerates combinations, partitions, subsets, index sets, and other combinatorial objects.
You can go up one level to the C++ source codes.