How Simple Algorithms can Solve Latin Square Completion-Type Puzzles Approximately

Kazuya Haraguchi, Hirotaka Ono

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Among many variations of pencil puzzles, Latin square Completion-Type puzzles (LSCPs) are quite popular for puzzle fans. Concerning these puzzles, the solvability has been investigated from the viewpoint of time complexity in the last decade; it has been shown that, in most of these puzzles, it is NP-complete to determine whether a given puzzle instance has a proper solution. In this paper, we investigate the approximability of three LSCPs: Sudoku, Futoshiki and KenKen. We formulate each LSCP as a maximization problem that asks to fill as many cells as possible, under the Latin square condition and the inherent condition. We then propose simple generic approximation algorithms for them and analyze their approximation ratios.

Original languageEnglish
Pages (from-to)276-283
Number of pages8
JournalJournal of information processing
Volume23
Issue number3
DOIs
Publication statusPublished - Jan 1 2015

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Approximation algorithms
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All Science Journal Classification (ASJC) codes

  • Computer Science(all)

Cite this

How Simple Algorithms can Solve Latin Square Completion-Type Puzzles Approximately. / Haraguchi, Kazuya; Ono, Hirotaka.

In: Journal of information processing, Vol. 23, No. 3, 01.01.2015, p. 276-283.

Research output: Contribution to journalArticle

Haraguchi, Kazuya ; Ono, Hirotaka. / How Simple Algorithms can Solve Latin Square Completion-Type Puzzles Approximately. In: Journal of information processing. 2015 ; Vol. 23, No. 3. pp. 276-283.
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