Monday, March 23, 2009

My New Favorite Puzzle: Tentaizu


I found a new puzzle. New to me anyway. It's called Tentaizu. I found it in the in-flight magazine on the way home from vacation. Btw, Southwest's magazine has the best puzzle section that I've ever seen. Not a reason to buy a ticket, but a definite perk. Anyway, I was completely charmed by this game. I thought we would play one this week. Maybe if we get excited we can try to automate a solution technique. I also tried to find a website that generates these like those I've found for Sudoku and KenKen. No luck.

Here are the instructions from Southwest's magazine:
In each of the grids on this page, stars are
hiding in 10 of the 49 squares. Your task is
to determine the positions of the stars. The
numbers in the grid provide clues: A number
in a square indicates how many stars lie next
to the square—in other words, how many
adjacent squares (including diagonally adjacent
squares) contain stars. No square with
a number in it contains a star, but a star may
appear in a square with no adjacent numbers.

20 comments:

nuckleman81 said...

This seems to be a paper version of the game "Minesweeper," which you can find on most PCs.

In that game, however, you have a grid of blank squares, and you start clicking. This clears the blank, and shows you either a bomb, or the number of bombs which touch that square.

You work your way around, and if you ever click on a bomb, you lose.

HM said...

I remember that game from the old windows! I take it that it's still there. I have to check my PC at work.

Have you tried working a Tentaizu out? It seems like a slightly different information situation. Each square you unveil in Minesweeper gives you more information, whereas you're given all you're going to get at the beginning of this game. I would be interested to know if you think this or Minesweeper is harder?

nuckleman81 said...

Well, presently, I'd say that this one is harder. As it stands, I can find no starting-off point from which to work. But I haven't given it my full focus.

HM said...

I was the same way when I was working mine on the plane. I remember thinking how do I start this thing? I was a little luckier: one of my squares had a zero on it.

Lance said...

What a coincidence; I just found this puzzle a few days ago on a Southwest magazine as well.

There seems to be a pretty easy starting technique. There are only 10 stars. Therefore, you can find three to five regions where all the stars must be located. For this puzzle, you could circle the five squares around the top 3, the five squares around the 3 on the right in the middle, the eight squares around the 3 in the middle of the puzzle, and the five squares around the 1 in the top left.

Go ahead and cross everything else out. You already have general locations of all 10 stars. I found this puzzle difficult at first, but after realizing this trick I was able to complete five in about three or four minutes each.

Tinyc Tim said...

A Java applet for Tentaizu is at http://www.cs.williams.edu/~bailey/tentaizu/

HM said...

Thanks, Tim! Unlimited Tentaizu fun.

Lance, I think your technique is based on the assumption that all the stars are adjacent to at least on of the number-squares. It's possible to have stars that aren't adjacent to any square, right?

Jeremy Jones said...

That's true, but Lance's method will help you get started, I think. It helps you decide where some of them definitely are.

However, you eventually reach a point where you have a problem. At least, I've found that to be true.

Lance said...

Ah, good point. However, you'll immediately be able to tell if that's the case, right? You won't be able to find enough areas to circle that add up to 10. Then, I guess, it doesn't work, but it makes the other ones easier.

Anonymous said...

For the non obvious ones you have to use logic to get it right with no guess work. For example the middle 3 on this board...only 5 options but it can't be the top two or the bottom right two so therefore the bottom left must be a star.....you can use that logic all over the place to open up the board.

Anonymous said...

i solved all the ones on the plane
you never have to guess

ericrao said...

never mind
i was thinking of a different game i did in the magazine with arrows and numbers in columns
sorry about the last post

Anonymous said...

never mind
i was thinking of a different game i did in the magazine with arrows and numbers in columns
sorry about the last post

Kevin said...

These puzzles differ from minesweeper in that you actually have to use logic. Or maybe better said, logic will help you finish the puzzle. Minesweeper was fun, but very frustrating because you often ended up having to GUESS between two cells at the end of a puzzle. Tenzaiku is much better in my opinion.

nadine said...

This puzzle is also on the app store, you should try it. Go to this site: http://www.poisonslug.com/tentaizu/

Anonymous said...

We have Tentaizu in Android market. We are extending to other platfors too. Tentaizu Lite is the free version of the game Tentaizu. It provide an oppurtunity to test the game if you like or not.

Tentaizu differs from minespweper. There is no randomness. It let you think from beginning. Each tentaizu game has a unique solution which is also a clue to guide to the solution. It needs both analtyical and reasonal thinking at the same time.

The game we (Ronsac) are providing has 5 different challange level and four different board sizes, 4x4, 5x5, 6x6, 7x7.

Tentaizu differs from Sudoku. As known Sudoku is just reasoning. Since Tentaizu allows you think in both analytical and logical, the solution can be reached in quicker way with more taste if you master it a little. It gives you a short but deep mind gymnastics in a spare time or in a time you would like to focus for a diffrent subject for a short time.

Phenix Yu said...

I have just released my first indie title 'Tentaizu' on iOS for free.

Different from the regular Tentaizu, however; a special reward system is designed. Please find more in the press release. http://tentaizu.tumblr.com/

Thank you for your time and I look forward to hearing from you!

Hendree Milward said...

Nice App!!

J. Jones said...

Wow! Blast from the past!

J. Jones said...

Wow, what a blast from the past! Hey guys!