This is the 64 bit version of zchaff. [2007.3.12] Fixed the inefficiency bug in zverify_df. Thanks to Allen Van Gelder and Tjark Weber. [2004.11.15 Simplified] This is just a simplified version of 2004.5.13. Many portions of dead codes are removed. Some of codes are re-written and re-formatted for easy reading. You might experience a little speedup. Please switch back to 2004.5.13 if the functionalities you need are removed in the simplified version. [2004.5.13] Some performace update. This is the version we used for SAT04 competition. Please consult our website for the detailed description. [2003.12.04] Fixed: 1. Various bugs in add_clause_incr(). We would like to thank Alexander Smith from University of Toronto for his suggestion and experiments on this issue. 2. SAT_HOOK added. 3. unset_force_terminate added. [2003.11.04] Fixed: 1. Compile under g++ 3.3 and above 2. Assertion error for certain instances in core extraction 3. A typo in run_till_fix. Now it takes the second argument as the max number of iterations to run as intended. [2003.10.09] Fixes in this release: 1. Bug fixed for time overflow after 2147 seconds. 2. The Perl script run_till_fix is updated such that it works for cnf files located in other directory. 3. zverify_df.cpp now also verifies the conflict clause given in resolve_trace with the one constructed by zverify itself using the information given in resolve_trace. [2003.7.22] NOTE: If your code is in C instead of C++, please use SAT_C.h instead of SAT.h as the header file. This is a new (as of June, 2003) release of zchaff, a SAT solver from Princeton University. The main difference between this one and the previous (2001.2.17) version are listed in the following: 1. This version of zchaff has incremental SAT solving capability In practice, many SAT instances are related in the sense that they only differ in a small number of clauses. Zchaff can solve a set of such instances incrementally, leveraging the knowledge (clauses) learned from previous runs to help current runs. This feature can only be invoked through the functional call interface. Please read SAT.h for more information about assigning clauses with Group IDs and how to delete clause or add clauses by groups. 2. This version of zchaff is certifiable Now zchaff can produce a verifiable trace that can be checked by a third party checker. To invoke this, modify zchaff_solver.cpp and uncomment #define VERIFY_ON and compile again. Now zchaff will produce a trace called resolution_trace after each run and this can be checked by zverify_bf or zverify_df, which are two checkers based on breadth-first and depth-first search. 3. This version of zchaff can produce an unsatisfiable core from an unsatisifable formula Unsatisfiable core extraction can be useful for some applications. This version of zchaff implement the idea presented in our SAT 2003 paper about extracting unsat cores. 4. This version can compile under gcc 3.x. 5. This version fixed a couple of serious bugs in the previous version. (But may have introduced other bugs :(). How to Install: Use "make" to compile, or "make all" to compile zchaff with extra utilities (e.g. core extractor, verifier). It should work without any problem under Linux, Cygwin or Solaris. To compile a native Windows executable, Open Visual Studio .Net, create a project, and add these files into the project: zchaff_base.cpp, zchaff_cpp_wrapper.cpp (this can be obtained by rename zchaff_wrapper.wrp to zchaff_cpp_wrapper.cpp and delete all occurance of "EXTERN" in the file.) zchaff_dbase.cpp zchaff_solver.cpp zchaff_utils.cpp sat_solver.cpp Also, modify files that contain headers "sys/*.h". Delete those troublesome headers, replace them with "#include ", and replace the code for function get_cpu_time() with: double get_cpu_time(void) { return (double)clock()/(double)(CLOCKS_PER_SEC); } This function will overflow after 2147 seconds. So the reported time may not be correct. This is a temporary solution and hopefully we will fix it in the future. MSVC will report a lot of warnings. Hopefully none is serious. :(. As you suspected, zchaff is not tested under native Windows enviroment. But anyway, this is the hack. How to use: the main executable is zchaff. The command line is zchaff CNF_FILE [TimeLimit] Other executables will print out a help info when executed with no argument. run_till_fix can obtain a small core by iteratively run core extraction. Do turn VERIFY_ON in zchaff_solver.cpp when compile. For any questions or bug reports, please send email to Yogesh Mahajan at yogism@Princeton.EDU Thanks. The SAT Group at Princeton University