Recent progress in heuristic search: a case study of the four-peg towers of Hanoi problem

  • Authors:

  • Richard E. Korf;Ariel Felner

  • Affiliations:

  • Computer Science Department, University of California, Los Angeles, Los Angeles, CA;Department of Information Systems Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel

  • Venue:
  • IJCAI'07 Proceedings of the 20th international joint conference on Artifical intelligence
  • Year:
  • 2007

Quantified Score

Hi-index 0.00

Visualization

Abstract

We integrate a number of new and recent advances in heuristic search, and apply them to the fourpeg Towers of Hanoi problem. These include frontier search, disk-based search, parallel processing, multiple, compressed, disjoint, and additive pattern database heuristics, and breadth-first heuristic search. New ideas include pattern database heuristics based on multiple goal states, a method to reduce coordination among multiple parallel threads, and a method for reducing the number of heuristic calculations. We perform the first complete breadth-first searches of the 21 and 22-disc fourpeg Towers of Hanoi problems, and extend the verification of "presumed optimal solutions" to this problem from 24 to 30 discs. Verification of the 31-disc problem is in progress.