Well-structured program equivalence is highly undecidable
نویسندگان
چکیده
منابع مشابه
The Hurwitz Equivalence Problem Is Undecidable
In this paper, we prove that the Hurwitz equivalence problem for 1-factorizations in F2⊕F2 is undecidable, and as a consequence, the Hurwitz equivalence problem for ∆-factorizations in the braid groups Bn, n ≥ 5 is also undecidable.
متن کاملEquivalence of DATALOG Queries is Undecidable
D Datalog is a powerful query language for relational databases [lo]. We consider the problems of determining containment, equivalence, and satisfiability of Datalog queries. We show that containment and equivalence are recursively unsolvable. This should be contrasted with the work of Aho, Sagiv, and Ullman on relational queries [l]. Satisfiability is easily decidable for Datalog queries. We a...
متن کاملThe Simplest Language Where Equivalence of Finite Substitutions Is Undecidable
We show that it is undecidable whether two finite substitutions agree on the binary language a∗b. This in particular means that equivalence of nondeterministic finite transducers is undecidable even for two-state transducers with unary input alphabet and whose all transitions start from the initial state.
متن کاملSome Highly Undecidable Lattices
Let S be a Steinitz Exchange System with closure operation cl (see e.g. [5] for definitions). In this paper we examine the logical complexity of the first-order theory of the lattice of cl-closed subsets of S. (In the first-order language for lattices we use symbols for meet, join, and the elements zero and one.) As quantification over the elements of the lattice is quantification over some of ...
متن کاملEquivalence of linear, free, liberal, structured program schemas is decidable in polynomial time
A program schema defines a class of programs, all of which have identical statement structure, but whose expressions may differ. We define a class of syntactic similarity binary relations between linear structured schemas and show that these relations characterise schema equivalence for structured schemas which are linear, free and liberal. In this paper we prove that similarity implies equival...
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: ACM Transactions on Computational Logic
سال: 2012
ISSN: 1529-3785,1557-945X
DOI: 10.1145/2287718.2287726