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This content will become publicly available on January 1, 2026

Title: Reencoding Unique Literal Clauses
We present a lightweight reencoding technique that augments propositional formulas containing implicit or explicit exactly-one constraints with auxiliary variables derived from the order encoding. Our approach is based on the observation that many formulas contain clauses where each literal appears only in that clause, and that these unique literal clauses can be replaced by the corresponding sequential counter encoding of exactly-one constraints, which introduces the same variables as the order encoding. We implemented the reencoding in the state-of-the-art SAT solver CaDiCaL with support for proof logging and solution reconstruction. Experiments on SAT Competition benchmarks demonstrate that our technique enables solving dozens of additional formulas. We found that shuffling a formula before reencoding harms performance. To mitigate this issue, we introduce a method that sorts literals within clauses based on the formula structure before applying our reencoding. The same technique also predicts whether reencoding is likely to yield improvements.  more » « less
Award ID(s):
2415773
PAR ID:
10629035
Author(s) / Creator(s):
; ;
Editor(s):
Berg, Jeremias; Nordström, Jakob
Publisher / Repository:
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Date Published:
Volume:
341
ISSN:
1868-8969
ISBN:
978-3-95977-381-2
Page Range / eLocation ID:
29:1-29:21
Subject(s) / Keyword(s):
Satisfiability solving auxiliary variables graph coloring Theory of computation → Automated reasoning
Format(s):
Medium: X Size: 21 pages; 1293946 bytes Other: application/pdf
Size(s):
21 pages 1293946 bytes
Location:
SAT 2025 in Glasgow
Right(s):
Creative Commons Attribution 4.0 International license; info:eu-repo/semantics/openAccess
Sponsoring Org:
National Science Foundation
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