Computing hypergraph width measures exactly
نویسندگان
چکیده
منابع مشابه
Computing hypergraph width measures exactly
Hypergraph width measures are a class of hypergraph invariants important in studying the complexity of constraint satisfaction problems (CSPs). We present a general exact exponential algorithm for a large variety of these measures. A connection between these and tree decompositions is established. This enables us to almost seamlessly adapt the combinatorial and algorithmic results known for tre...
متن کاملComputing rank-width exactly
We prove that the rank-width of an n-vertex graph can be computed exactly in time O(2n log n log log n). To improve over a trivial O(3 log n)-time algorithm, we develop a general framework for decompositions on which an optimal decomposition can be computed efficiently. This framework may be used for other width parameters, including the branch-width of matroids and the carving-width of graphs....
متن کاملHypertree width and related hypergraph invariants
Tree-width of graphs is a well studied notion, which plays an important role in structural graph theory and has many algorithmic applications. Various other graph invariants are known to be the same or within a constant factor of tree-width, for example, the bramble number or tangle number of a graph [4, 5], the branch-width [5], the linkedness [4], and the number of cops required to win the ro...
متن کاملClique-Width and Directed Width Measures for Answer-Set Programming
Disjunctive Answer Set Programming (ASP) is a powerful declarative programming paradigm whose main decision problems are located on the second level of the polynomial hierarchy. Identifying tractable fragments and developing efficient algorithms for such fragments are thus important objectives in order to complement the sophisticated ASP systems available to date. Hard problems can become tract...
متن کاملRelating two width measures for resolution proofs
A clause is a disjunction of literals. We use set notation; a set of literals denotes the clause that is their disjunction. The empty clause is denoted by . The width of a clause C, denoted |C|, is the number of literals in it. The width of a CNF formula F , denoted width(F ), is the maximum width of any clause in F . For a partial assignment ρ, C|ρ denotes the restriction of the clause C by ap...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Information Processing Letters
سال: 2012
ISSN: 0020-0190
DOI: 10.1016/j.ipl.2011.12.002