versat is a verified SAT solver.  We have proven statically that every
time versat says UNSAT, there is really a propositional refutation of
the input clause set.  See our 2012 VMCAI paper about this.

Versat is written in Guru, a research language with dependent types,
developed by Aaron Stump.  The distribution you are looking at
contains the C code generated for versat by the Guru compiler.  It
also contains the Guru sources.

Compile versat.c with a C compiler.  Please ignore the significant number
of generated warnings.

Versat expects the .cnf file (DIMACS format) to check for satisfiability
to be given on standard input, like ./versat < file.cnf.

Aaron Stump
March, 2015