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<title>Chaff algorithm</title>
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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Chaff algorithm</span></span>
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<p><b>Chaff</b> is an <a href="Algorithm" title="Algorithm">algorithm</a> for solving instances of the <a href="Boolean_satisfiability_problem" title="Boolean satisfiability problem">Boolean satisfiability problem</a> in programming. It was designed by researchers at <a href="Princeton_University" title="Princeton University">Princeton University</a>. The algorithm is an instance of the <a href="DPLL_algorithm" title="DPLL algorithm">DPLL algorithm</a> with a number of enhancements for efficient implementation.
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<div class="mw-heading mw-heading2"><h2 id="Implementations">Implementations</h2></div>
<p>Some available implementations of the algorithm in software are <code>mChaff</code> and <b><code>zChaff</code></b>, the latter one being the most widely known and used. zChaff was originally written by Dr. Lintao Zhang, hence the “z”. It is now maintained by researchers at <a href="Princeton_University" title="Princeton University">Princeton University</a> and available for <a href="Download" title="Download">download</a> as both source code and binaries on <a href="Linux" title="Linux">Linux</a>. zChaff is free for non-commercial use.
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<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>
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<ul><li>M. Moskewicz, C. Madigan, Y. Zhao, L. Zhang, S. Malik. <i><a rel="nofollow" class="external text" href="http://www.princeton.edu/~chaff/publication/DAC2001v56.pdf">Chaff: Engineering an Efficient SAT Solver</a></i>, 39th Design Automation Conference (DAC 2001), Las Vegas, ACM 2001.</li>
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</style><cite id="CITEREFVizelWeissenbacherMalik2015" class="citation journal cs1">Vizel, Y.; Weissenbacher, G.; Malik, S. (2015). "Boolean Satisfiability Solvers and Their Applications in Model Checking". <i>Proceedings of the IEEE</i>. <b>103</b> (11): <span class="nowrap">2021–</span>2035. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FJPROC.2015.2455034">10.1109/JPROC.2015.2455034</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:10190144">10190144</a>.</cite></li></ul>
<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>
<ul><li><a rel="nofollow" class="external text" href="http://www.princeton.edu/~chaff/zchaff.html">Web page about zChaff</a></li></ul>
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