#cnf #file-format #dimacs #convert-text #sat #codec

app cnfpack

Converts between the text based DIMACS CNF file format and the compressed binary Cnfpack format

2 releases

0.1.1 Mar 6, 2022
0.1.0 Aug 23, 2021

#527 in Compression

0BSD license

610 lines


github crates.io

Encoder and decoder for the Cnfpack format.

Converts between the text based DIMACS CNF file format and the compressed binary Cnfpack format.


Cnfpack is a compressed file format for CNF formulas. Converting a DIMACS CNF formula to and from Cnfpack maintains the order of clauses as well as the order of literals within clauses. Comments, optional whitespace or leading zeros in the DIMACS input are not stored.

Example Usage

# Download example instance
wget -nv https://gbd.iti.kit.edu/file/5fb0d1f02c02c6a7fb485707b637d7e4/bvsub_12973.smt2.cnf.xz
#> 2021-08-23 17:55:24 URL:https://gbd.iti.kit.edu/file/5fb0d1f02c02c6a7fb485707b637d7e4/bvsub_12973.smt2.cnf.xz [1559552/1559552] -> "bvsub_12973.smt2.cnf.xz" [1]
# Decompress `xz` file
xz -dk bvsub_12973.smt2.cnf.xz
# Convert to `cnfpack`
cnfpack bvsub_12973.smt2.cnf bvsub_12973.smt2.cnfpack
# Check file sizes
du -bh bvsub_12973.smt2.{cnf,cnf.xz,cnfpack}
#> 20M	bvsub_12973.smt2.cnf
#> 1.5M	bvsub_12973.smt2.cnf.xz
#> 2.2K	bvsub_12973.smt2.cnfpack
# Decompress and compute GBD hash to verify the formula
cnfpack -d bvsub_12973.smt2.cnfpack | tail +2 | head -c -1 | tr '\n' ' ' | md5sum
#> 5fb0d1f02c02c6a7fb485707b637d7e4 -
# ^ Matches the hash in the download URL


Make sure you have a working Rust toolchain and then run cargo install cnfpack to download, install and build the latest version. Alternatively I also provide binaries for some platforms.


This software is available under the Zero-Clause BSD license, see LICENSE for full licensing information.


Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this software by you shall be licensed as defined in LICENSE.


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