The shortest common nonsubsequence problem is NP-complete

The Maze Generation Problem is NP-complete

The Maze Generation problem has been presented as a benchmark for the Second Answer Set Programming Competition. We prove that the problem is NP–complete and identify relevant classes of unsatisfiable instances. The Maze Generation (MG) problem has been presented as a benchmark for the Second Answer Set Programming (ASP) Competition1. The problem has been placed in the NP category, which contai...

The transposition median problem is NP-complete

During the last years, the genomes of more and more species have been sequenced, providing data for phylogenetic reconstruction based on genome rearrangement measures, where the most important distance measures are the reversal distance and the transposition distance. The two main tasks in all phylogenetic reconstruction algorithms is to calculate pairwise distances and to solve the median of t...

The Cophylogeny Reconstruction Problem Is NP-Complete

The co phylogeny reconstruction problem is that of finding minimum cost explanations of differences between historical associations. The problem arises in parasitology, molecular systematics, and biogeography. Existing software tools for this problem either have worst-case exponential time or use heuristics that do not guarantee optimal solutions. To date, no polynomial time optimal algorithms ...

TEN ETUDES ON SHORTEST COMMON NONSUBSEQUENCE AND SUPERSEQUENCE APPROXIMATIONSy

The Graph Genus Problem is NP-Complete

The genus g(G) of a graph G is the smallest number g such that G can be embedded on the orientable surface of genus g. Given a graph G and a natural number k one may ask: Is g(G) I k? This problem, called the graph genus problem, is one of the remaining basic open problems, listed by Garey and Johnson 121, for which there is neither a polynomially bounded algorithm nor a proof that the problem ...