Maximum And- vs. Even-SAT

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Nakajima, Tamio-Vesa, Živný, Stanislav
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918358649143296
author Nakajima, Tamio-Vesa
Živný, Stanislav
author_facet Nakajima, Tamio-Vesa
Živný, Stanislav
contents A multiset of literals, called a clause, is \emph{strongly satisfied} by an assignment if \emph{no} literal evaluates to false. Finding an assignment that maximises the number of strongly satisfied clauses is NP-hard. We present a simple algorithm that finds, given a multiset of clauses that admits an assignment that strongly satisfies $ρ$ of the clauses, an assignment in which at least $ρ$ of the clauses are \emph{weakly satisfied}, in the sense that an \emph{even} number of literals evaluate to false. In particular, this implies an efficient algorithm for finding an undirected cut of value $ρ$ in a graph $G$ given that a directed cut of value $ρ$ in $G$ is promised to exist. A similar argument also gives an efficient algorithm for finding an acyclic subgraph of $G$ with $ρ$ edges under the same promise.
format Preprint
id arxiv_https___arxiv_org_abs_2409_07837
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Maximum And- vs. Even-SAT
Nakajima, Tamio-Vesa
Živný, Stanislav
Data Structures and Algorithms
A multiset of literals, called a clause, is \emph{strongly satisfied} by an assignment if \emph{no} literal evaluates to false. Finding an assignment that maximises the number of strongly satisfied clauses is NP-hard. We present a simple algorithm that finds, given a multiset of clauses that admits an assignment that strongly satisfies $ρ$ of the clauses, an assignment in which at least $ρ$ of the clauses are \emph{weakly satisfied}, in the sense that an \emph{even} number of literals evaluate to false. In particular, this implies an efficient algorithm for finding an undirected cut of value $ρ$ in a graph $G$ given that a directed cut of value $ρ$ in $G$ is promised to exist. A similar argument also gives an efficient algorithm for finding an acyclic subgraph of $G$ with $ρ$ edges under the same promise.
title Maximum And- vs. Even-SAT
topic Data Structures and Algorithms
url https://arxiv.org/abs/2409.07837