Author round-table 006

InterviewsAuthor round-table

About Nurikabe in the past and in the future.

The theme this time is Nurikabe. The guests are MINE, Ogawa Minori, and Momotereu. They make a lot of wonderful puzzles. From Nikoli we have NyanBaz and Nob. Momotereu is also on the Nikoli staff, but today, he came here as an author.

NyanBazFirst of all, your thoughts on Nurikabe. There are a variety of pencil puzzles in the world. Among them, how do you think Nurikabe places?

MINEBoth to make and to solve, I like Nurikabe the best.

Ogawa MinoriFor me it's the second best. My first is Nansuke.

NobHe would say that, Ogawa Minori is a wizard with Nansuke.

MomotereuIt's second best for me too. Fillomino comes in first. But the puzzle I have made the most of is Nurikabe.

NobAbout Vol. 50 to 60 of Puzzle Communication Nikoli, Nurikabe the giant was always done by Momotereu.

MINEYes yes. I solved that thinking all along that Momotereu had to be crazy.

MomotereuMy first contribution was for Vol. 52 (Published 1995). I sent in a giant size Nurikabe then.

MINEThe first puzzle contribution is a giant size puzzle! That's crazy.

MomotereuFrom when did you contribute puzzles, Minori?

Ogawa MinoriFrom Vol. 42.

MINEIt's about the same as me. My first published puzzle was in Vol. 43.

MomotereuDid Nurikabe exist already then?

NobIt would have been there. Nurikabe was born in the Nikoli thirties. (Note: It was Vol. 33 precisely. )

Ogawa MinoriI contributed Nurikabe from the beginning. But the first time, nothing got published. (laughs)

NyanBazThe Nurikabe from Ogawa Minori has a lot of diagonal lining up.Was it like that from the old days?

Ogawa MinoriNo, the beginning was different. Then there were many problems that arranged numbers symmetrically.

NobSymmetry was popular then.

NyanBazRecently you don't see it very much.

MINEI hardly make you notice except when I arrange the numbers super neatly.

Ogawa MinoriIt's difficult to make symmetric placements. I did it by trial and error, and that became the present style. The advantage in lining up things diagonally is that some of the cells are set immediately.

MINEThe issue number of the magazine was included in the Momotereu problems. For example, if it was Vol. 52, the number 52 appeared somewhere.

MomotereuI did that. I also made problems that overused one number.

MINEThat is possible with Nurikabe. Nurikabe makes it easy to use big numbers like 50 or 60. It's absolutely impossible in Kakuro and Sudoku. When it's Shikaku, it isn't impossible either.

NobWhen it's a prime number, Shikaku is difficult. For example 59.

NyanBazThat is difficult all right. 59 would have to be 1x59 or 59x1. (laughs)

MINEI like to use the white cells which occurr somewhere else in those numbers. I like to extend white cells from different places and fit them into a big number. It's an advantage of Nurikabe to be able to do such things. But it's limited to large size puzzles.

NobA black cell can't be alone, black cells have to hang together. Do you like it better when it is the white cells that set the pace?

MINEYes. When I make or solve Nurikabe, I don't think a lot about black cells. I watch the connections between white cells. I think in a way that avoids to divide the board by the white cells will show the places where the black cells go.

MomotereuI'm the opposite. I watch black cells mainly.

Ogawa MinoriI watch white cells and black cells alternately. I find it interesting how they extend and spread together.

NyanBazNurikabe means painting walls. Nurikabe is a puzzle of the walls when I look at the name.

MINEIn a hard problem, there are times where the black cells of some area isn't decided yet, but where the connections between the white cells are almost fixed. In such a situation, it's easy to understand that we have to see the connection between white cells and look for the positions of the black cells which are settled to prevent totally dividing the board.

NobThat's a quite advanced technique. The black cells are linked in a continuous wall. It's the equivalent of not dividing the board by white cells. Nurikabe is the puzzle where both white cells and black cells extend little by little. So in Nurikabe you have to watch both the white cells and the black cells.

NyanBazHowever, this keeping an eye on connections between white cells may be overlooked or forgotten. It's hard to understand from how the rules are written.

MINEActually, there are many many people overlooking that. There is even a puzzle author who hasn't been really conscious of the relations between the white cells until recently.

NyanBazSomeone who comes to a dead end with a difficult problem may follow how the white cells go and find the solution.

MINEI'm pretty sure that approach will be successful.

NyanBazDo you solve Nurikabe problems that other authors made?

Ogawa MinoriI'm sorry, no. I don't solve others very much.

MINEI solve them a lot. I solve most of the Nurikabe on nikoli.com.

MomotereuI solve anything too.

NyanBazIs there a Nurikabe author that you pay special attention to?

Ogawa MinoriI don't pay attention to whose problem it is. I don't solve so many Nurikabe in fact.

MINEIn nikoli.com, I think that Yuichi Saito does bizarre things. I think that he is changed from his former self. I imagine that something may have occured in his private life. (laughs)

NobSomething wonderful is bound to happen in his life.

NyanBazHow about you Momotereu?

MomotereuI pay attention to Guten.

NobWhat is it in Guten that you like?

MomotereuHe likes to impose his favorite way of development insistently. I like that. From what I recall, no new solving methods have come out of Nurikabe.

NobThere are many methods we have prohibited with Nurikabe. For example, when one blank space becomes a white cell, but there is only one number that can be connected to this white cell. There are some contributions that center on this kind of thing and apply this method. Unfortunately they are not published.

MINEI think it is reasonable not to accept that method. It would lead to so many other complications.

NobSure. We don't want that.

MINENurikabe has so few solving methods, and I'm still amazed to see that Nurikabe has survived for all this long time.

NobIt may be less popular than before. There has been no new Nurikabe Pencil Puzzle Book published for a while. But Nurikabe is popular in nikoli.com.

Ogawa MinoriYour fingers don't get dirty when you solve Nurikabe on a PC. That is one good point.

NyanBazWell, Nurikabe may have survived because it appeared on computers. How about the future of Nurikabe? Will it continue forever into the future?

Ogawa MinoriI think that it will continue. Because there isn't any good puzzle to replace Nurikabe.

MINEI think it'll continue like a long continuing TV drama series like Mito Komon. It's similar to aiming at getting on the air a million times. (laughs)

NobMito Komon! The actor playing the chief character in the series was replaced several times, but a chief character was always Mito Komon, and the drama continues.

MINEThere will be new people making the problems, the appearance and direction will change, but the foundations don't change. White cells and black cells stretching out, white cells looking for the right number.

MomotereuHowever, I still think that we have to do new things. I thought that MINE has been doing new things here.

MINENothing new from me. My aim is like with Mito Komon. (laughs)

NobDo you think there are new solving methods for Nurikabe?

MomotereuAll the methods are already out there now. But I can devise new ways of presentation.

NyanBazDo you have any thing you want to do with Nurikabe?

MomotereuYes I have something. In 2009, there was a Nurikabe world meeting in Spain. Worldwide, meetings for Nurikabe on this planet have so far only been held in Spain.

MINEMomotereu went to Spain, too.

NobWhat did they call you there? Momo?

MomotereuYes I was called Momo. It doesn't matter what I'm called. There were people there who solved Nurikabe for the first time, they participated in the meeting. I explained the rules and I learned that Nurikabe is difficult to understand. They can understand the numbers where they form a diagonal. They can understand cracks between numbers. They can understand what goes on around the number 1. However, they can't get it all up to there. I want to hand on these skills. I want to disseminate Nurikabe to everywhere in the whole world.

NyanBazHow about you Minori?

Ogawa MinoriI want to continue making Nurikabe just like it is, solid and stable. I don't want to reform something. I leave reformations to other people.

NobMinori you don't have to change anything. Do you have something you want to do with Nurikabe MINE?

MINEMinori has said what I want to say. (laughs) I intended to say that I want to make Nurikabe for another 30 years. Talking about techniques, I get absorbed in choosing two to one. (The situation where there are two possibilities for a number to be connected when there is one white cell already, and it isn't readily settled.) I want to widen the choice to 3 and 4, to 8 even.

NyanBazThat is a way out enthusiastic ambition. We are getting close to the end, I'll ask you for a word to Nurikabe fans all over the world and for the people who will solve Nurikabe from now on.

MINEI'm aiming at large size problems where there is a story and which gives a sense of accomplishment. I want to offer surprises in a small sized problem. I'll be really happy if I can deliver on my aims and hopes.

Ogawa MinoriNurikabe offers a balance with places where you can advance slowly and places where to can rush along at full speed. First of all, please enjoy doing Nurikabe.

NyanBazMomotereu goes last. I expect to hear a comment on a vast and wonderful scale.

MomotereuHmmm. I will see to make Nurikabe popular throughout the world! From Japan and Spain -- to the world!

NyanBazThank you for today.


Discussion on Jan 2010 Published on Mar 28, 2013

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