Sudoku (and chess?)

All Things Chess
1

One day, recently, I was bored, really bored. Tired of chess, tired of the news, not even in the mood to read a novel. So I launched google play, and browsed the games section.

Before long, I came across Sudoku. A numbers game I’d pretty much ignored over the years. Not having any particular interest in it. But out of boredom and bit of curiosity, I installed Sudoku.

My first few games were horrendous, but as an added challenge, I decided to play it without taking notes. Not sure if your allowed to take notes or not, but clearly some people do.

After a few days, I worked myself up to medium strength. -I’ve yet to successfully solve a hard puzzle though. I spent nearly 90 minutes on the last one, not choosing a number until I was absolutely certain I had the number correct. Sadly, it can take a very long time before it becomes obvious that being “absolutely certain” doesn’t mean it’s correct.

Anyway, in solving Sudoku puzzles without notes, means I’m constantly scanning the board over and over for lines. Mainly, for me anyway, sudoku is a puzzle of subtraction. That is, your constantly visualizing trying to fill in lines by subtracting lines (and boxes in those lines) of lines your not allowed to fill in. For example, a square, which is 9 boxes, has say, 5 empty boxes in it, your trying to find lines that block out the boxes you can’t fill in yet. Eventually you isolate a box that looks promising. -At the easy levels, that’s about all the problems consists of. As you get harder puzzles, you have to start juggling more and more numbers in your head, since there are times when the only way to isolate a box is to juggle say 3 boxes with 3 numbers, so it gets pretty chaotic in your head if your not using notes.

Back to chess.

It’s REALLY helped my chess game by reducing my tunnel vision in chess. Even GM’s can suffer a bit of tunnel vision, and even lose games because of it. But because Sudoku forces me to constantly visualize lines and combinations, it really improved my chess playing.

Plus it’s a nice break from the chess board.

I can’t say it’s helped me find better combinations or more complex combinations in chess, but it does help me to avoid more lines that lead to negative results, or find a way to neutralize an opponent’s move that looks very strong at first glance.

Even if I never solve a hard puzzle, even the medium puzzles are complex enough to put a nice challenge for my brain. The most complex medium puzzle will have 1 or 2 times where I have to juggle maybe 2 numbers for 2 boxes at once. Without taking notes, for me, it comes across as a nice mental challenge. I would think if I solve enough medium puzzles, I might eventually be able to solve a hard puzzle without taking notes. But not anytime soon, I’ve only started doing Sudoku for about a week.

2

If you used an 8 x 8 board, 4 white pieces and 4 black pieces, you could do Sudoku-Chess.

3

Another one bitten by the Sudoku bug! I have a book full of hard puzzles that I take along when I’m traveling for when there’s nothing to do. I can usually solve them now, but they’re … hard, so it keeps me busy and out of trouble.

Funny that an old chess player like myself would be looking around for other things to do to pass the time. But I also used to play minesweeper, and after that, Web Boggle (wordsplay.net).

4

Take a look at this old thread.

Spoiler alert: If you want to work it out by yourself, look at only the first post in the thread, because the solution is given later.

The second through fifth posts are harmless. If you get stuck, the first hint appears at the sixth post.

Bill Smythe

5

I adapted a solver if you get really stumped. sudoku.htm

6

Do you take notes when solving hard puzzles?

7

I try not to, and I do them in pen rather than pencil. But I do get stumped sometimes. I have two different ways of taking notes. One of them involves writing little numbers in the corner of each square, to be scratched out later when I figure out what REALLY belongs in that square. The other method involves a separate sheet of paper. Write two 9x9 squares on the sheet. Pick some squares that look crucial, i.e. “Either this one is 3 and that one is 8, or this one is 8 and that one is 3, and if I knew which, I could really make progress.” Then use one square to further develop one alternative, use the other square to further develop the other alternative. Sooner or later one of two things will happen: (a) One of the alternatives will turn out to be impossible. Go back to the original board and start working with the other alternative. (b) Both the alternatives will end up putting the same number X in square Y. Go back to the original board, put that number in that square, and see if that helps you make progress.

The first method, writing little numbers in the corners of the squares, is less effort and less overhead, but I am not always sure whether it helps or hinders me, and besides, when I’m done, all those little scratched-out numbers are unsightly :slight_smile: The second method, with the separate sheet of paper, is 100% effective, but I have to have plenty of spare time (not to mention a spare sheet of paper).

Of course, if I can solve the whole puzzle without taking any notes, I feel better about it. But, can’t always do that!

8

The Sunday Washington Post has samurai Sudoku. It is essentially 5 Sudoku puzzles with the outer 4 all tied together by the inner one. They rank them from 1 to 5 stars with 5 being the hardest. I guarantee that trying to do a 5 star one is several hours of incredible fun

9

More fun that chess?? :sunglasses:
I’m waiting for this thread to be pulled for not contributing to the advancement of chess.

10

Sudoku is problem solving ,pattern recognition etal so very similar to chess.However playing blitz chess with a friend is and always will be the best

11

I’m locking this topic because it doesn’t have much to do with chess, although the point has been made that the thinking process is similar in some ways.