Note: on universally easy classes for NP-complete problems

  • Authors:
  • Erik D. Demaine;Alejandro López-Ortiz;J. Ian Munro

  • Affiliations:
  • MIT Laboratory for Computer Science, 200 Technology Square, Cambridge, MA;Department of Computer Science, University of Waterloo, Waterloo, Ont., Canada N2L 3G1;Department of Computer Science, University of Waterloo, Waterloo, Ont., Canada N2L 3G1

  • Venue:
  • Theoretical Computer Science
  • Year:
  • 2003

Quantified Score

Hi-index 5.23

Visualization

Abstract

We explore the natural question of whether all NP-complete problems have a common restriction under which they are polynomially solvable. More precisely, we study what languages are universally easy in that their intersection with any NP-complete problem is in P (universally polynomial) or at least no longer NP-complete (universally simplifying). In particular, we give a polynomial-time algorithm to determine whether a regular language is universally easy. While our approach is language-theoretic, the results bear directly on finding polynomial-time solutions to very broad and useful classes of problems.