著者

Chuzo Iwamoto

雑誌

情報処理学会論文誌 (ISSN:18827764)

巻号頁・発行日

vol.54, no.12, 2013-12-15

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Yosenabe is one of Nikoli's pencil puzzles, which is played on a rectangular grid of cells. Some of the cells are colored gray, and two gray cells are considered connected if they are adjacent vertically or horizontally. A set of connected gray cells is called a gray area. Some of the gray areas are labeled by numbers, and some of the non-gray cells contain circles with numbers. The object of the puzzle is to draw arrows, vertically or horizontally, from all circles to gray areas so that (i) the arrows do not bend, and do not cross other circles or lines of other arrows, (ii) the number in a gray area is equal to the total of the numbers of the circles which enter the gray area, and (iii) gray areas with no numbers may have any sum total, but at least one circle must enter each gray area. It is shown that deciding whether a Yosenabe puzzle has a solution is NP-complete.------------------------------This is a preprint of an article intended for publication Journal ofInformation Processing(JIP). This preprint should not be cited. Thisarticle should be cited as: Journal of Information Processing Vol.22(2014) No.1 (online)DOI http://dx.doi.org/10.2197/ipsjjip.22.40------------------------------

著者

Chuzo Iwamoto Tatsuaki Ibusuki

雑誌

情報処理学会論文誌 (ISSN:18827764)

巻号頁・発行日

vol.59, no.4, 2018-04-15

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Dosun-Fuwari is one of Nikoli's pencil puzzles, which is played on a rectangular grid of cells. Some of the cells are colored black, and the remaining cells are divided into rooms. The purpose of the puzzle is to place balloons and iron balls according to the following rules: Place one balloon and one iron ball in each room. Balloons (resp. iron balls) are light and float (heavy and sink), so they must be placed in the top (bottom) row of the grid of cells, or in a cell right under (over) a black cell or right under other balloons (over other iron balls). It is shown that deciding whether a Dosun-Fuwari puzzle has a solution is NP-complete.------------------------------This is a preprint of an article intended for publication Journal ofInformation Processing(JIP). This preprint should not be cited. Thisarticle should be cited as: Journal of Information Processing Vol.26(2018) (online)DOI http://dx.doi.org/10.2197/ipsjjip.26.358------------------------------

著者

Chuzo Iwamoto

出版者

一般社団法人 情報処理学会

雑誌

Journal of Information Processing (ISSN:18826652)

巻号頁・発行日

vol.22, no.1, pp.40-43, 2014 (Released:2014-01-15)

参考文献数

20

被引用文献数

2 15

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Yosenabe is one of Nikoli's pencil puzzles, which is played on a rectangular grid of cells. Some of the cells are colored gray, and two gray cells are considered connected if they are adjacent vertically or horizontally. A set of connected gray cells is called a gray area. Some of the gray areas are labeled by numbers, and some of the non-gray cells contain circles with numbers. The object of the puzzle is to draw arrows, vertically or horizontally, from all circles to gray areas so that (i) the arrows do not bend, and do not cross other circles or lines of other arrows, (ii) the number in a gray area is equal to the total of the numbers of the circles which enter the gray area, and (iii) gray areas with no numbers may have any sum total, but at least one circle must enter each gray area. It is shown that deciding whether a Yosenabe puzzle has a solution is NP-complete.