TY - GEN
T1 - Approximability of Latin square completion-type puzzles
AU - Haraguchi, Kazuya
AU - Ono, Hirotaka
N1 - Funding Information:
This work is partially supported by JSPS KAKENHI Grant Number 24106004, 25104521 and 25870661.
PY - 2014
Y1 - 2014
N2 - Among many variations of pencil puzzles, Latin square Completion-Type puzzles (LSCP), such as Sudoku, Futoshiki and BlockSum, 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 LSCP. We formulate LSCP as the 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 LSCP and analyze their approximation ratios.
AB - Among many variations of pencil puzzles, Latin square Completion-Type puzzles (LSCP), such as Sudoku, Futoshiki and BlockSum, 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 LSCP. We formulate LSCP as the 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 LSCP and analyze their approximation ratios.
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U2 - 10.1007/978-3-319-07890-8_19
DO - 10.1007/978-3-319-07890-8_19
M3 - Conference contribution
AN - SCOPUS:84903697629
SN - 9783319078892
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 218
EP - 229
BT - Fun with Algorithms - 7th International Conference, FUN 2014, Proceedings
PB - Springer Verlag
T2 - 7th International Conference on Fun with Algorithms, FUN 2014
Y2 - 1 July 2014 through 3 July 2014
ER -