The STO-problem is NP-hard
✍
Krzysztof R. Apt; Peter van Emde Boas; Angelo Welling
📂
Article
📅
1994
🏛
Elsevier Science
🌐
English
⚖ 209 KB
A finite set of term equations \(E\) is called subject to the occur-check (STO) if a sequence of actions of the Martelli-Montanari unification algorithm starts with \(E\) and ends with a failure due to occur-check. We prove here that the problem of deciding whether \(E\) is STO is NP-hard.