,
Chu-Min Li
,
Sami Cherif
,
Shuolin Li
Creative Commons Attribution 4.0 International license
Maximum Satisfiability (MaxSAT) is an optimization extension of the Satisfiability (SAT) problem. In Branch-and-Bound (BnB) MaxSAT solving, the quality of the lower bound estimation is critical for effective search space pruning. State-of-the-art BnB solvers typically estimate this bound by identifying disjoint inconsistent subformulas (cores) via Unit Propagation (UP). However, a limitation of this standard approach is that UP fails to detect cores that exhibit complex dependencies with already identified cores. In this paper, we propose a further lookahead algorithm that leverages pre-detected cores to uncover additional disjoint inconsistencies, thereby tightening the lower bound. Experimental results demonstrate that the proposed algorithm significantly tightens the lower bound, enabling the state of the art BnB solver MaxCDCL to solve more instances.
@InProceedings{zhang_et_al:LIPIcs.CP.2026.60,
author = {Zhang, Jialu and Li, Chu-Min and Cherif, Sami and Li, Shuolin},
title = {{Enhanced Lower Bound Computation in Branch-and-Bound for MaxSAT}},
booktitle = {32nd International Conference on Principles and Practice of Constraint Programming (CP 2026)},
pages = {60:1--60:18},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-432-1},
ISSN = {1868-8969},
year = {2026},
volume = {379},
editor = {Beldiceanu, Nicolas},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CP.2026.60},
URN = {urn:nbn:de:0030-drops-266935},
doi = {10.4230/LIPIcs.CP.2026.60},
annote = {Keywords: Maximum Satisfiability, Branch and Bound, Lower Bound}
}
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