pax_global_header00006660000000000000000000000064146132760310014515gustar00rootroot0000000000000052 comment=effa1dcce85c878236f8313133dff1a2b766cd7c LICENSE000066400000000000000000000022401461327603100120640ustar00rootroot00000000000000Copyright (c) 2014 Marijn Heule and Nathan Wetzler, The University of Texas at Austin. Copyright (c) 2015-2016 Marijn Heule, The University of Texas at Austin. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Makefile000066400000000000000000000007551461327603100125300ustar00rootroot00000000000000FLAGS = -DLONGTYPE all: drat-trim lrat-check compress decompress gapless drat-trim: drat-trim.c gcc drat-trim.c -std=c99 -O2 -o drat-trim lrat-check: lrat-check.c gcc lrat-check.c -std=c99 $(FLAGS) -O2 -o lrat-check compress: compress.c gcc compress.c -std=c99 $(FLAGS) -O2 -o compress decompress: decompress.c gcc decompress.c -std=c99 $(FLAGS) -O2 -o decompress gapless: gapless.c gcc gapless.c -std=c99 -O2 -o gapless clean: rm drat-trim lrat-check compress decompress gapless README.md000066400000000000000000000312131461327603100123400ustar00rootroot00000000000000# The DRAT format and DRAT-trim checker The proof checker DRAT-trim can be used to check whether a propositional formula in the DIMACS format is unsatisfiable. Given a propositional formula and a clausal proof, DRAT-trim validates that the proof is a certificate of unsatisfiability of the formula. Clausal proofs should be in the DRAT format which is used to validate the results of the SAT competitions. The format is defined below. The DRAT format and the corresponding checker DRAT-trim are designed based on the following goals: 1) It should be easy to emit clausal proofs to ensure that many SAT solvers will support it; 2) proofs should be compact to reduce the overhead of writing the proof and to make sure that the proof can be stored; 3) proof validation should be efficient; and 4) all techniques used in state-of-the-art SAT solvers should be expressible in the format. Regarding the last point, several techniques used in state-of-the-art SAT solvers cannot be expressed using resolution. The DRAT format is therefore a generalization of Extended Resolution. In short, each step in a clausal proof is either the addition or the deletion of a clause. Each clause addition step should preserve satisfiability, which should be computable in polynomial time. The polynomial time checking procedure is described in detail below. Clause deletion steps are not checked, because they trivially preserve satisfiability. The main reason to include clause deletion steps in proofs is to reduce the computational costs to validate proofs. ## Getting started The DRAT-trim proof checker can be compiled using: `make` . usage: `./drat-trim [INPUT] [] [