Sudoku

Timing TBLR Sudoku, 2/12/10-2/25/10

I wondered to myself how long I will continue this series of posts, and I’m currently thinking that if I go three periods of two weeks without a new personal best, that I will quit writing these posts.

For those who are just tuning in, this is the fifth of a series of posts occuring once every two weeks. In these posts, I show how long it takes for me to do a Sudoku puzzle with the additional restriction of having to fill in the numbers in top-to-bottom, left-to-right order. Hence the name TBLR Sudoku.

2/25/10 – 4-Star Sudoku in the Star-Tribune, top-to-bottom, left-to-right, 52:37
2/24/10 – 3-Star, 34:17, Personal Best +2:31
2/23/10 – 2-Star, Fail. Not really sure what that was about.
2/22/10 – 1-Star, 25:06, PB +6:53
2/21/10 – Didn’t do the puzzle
2/20/10 – Didn’t do the puzzle
2/19/10 – 5-Star, 40:02, PB +0:04
2/18/10 – 4-Star, 28:52, 5:05 improvement on previous PB
2/17/10 – 3-Star, 44:13, PB +11:27
2/16/10 – 2-Star, 37:31, PB +17:07
2/15/10 – 1-Star, 25:46, PB +7:33
2/14/10 – 5-Star, Fail
2/13/10 – 6-Star, 45:09, 8:29 improvement on previous PB
2/12/10 – 5-Star, 37:39, 2:19 improvement on previous PB

Here are the updated personal bests:

1-Star: 18:13, 11/23/09
2-Star: 20:24, 1/12/10
3-Star: 31:46, 1/20/10
4-Star: 28:52, 2/18/10
5-Star: 37:39, 2/12/10
6-Star: 45:09, 2/13/10

I do these puzzles to build up my skill for contemplating the puzzle of my existence.

Technorati: Sudoku

Timing TBLR Sudoku, 1/29/10-2/11/10

I’ve modified my strategy to scan the rows, columns and 3 X 3 boxes to see if there are any with six or more numbers in them. If there aren’t any, then I just start my usual scan. Drew Brees said that the Saints took what the Colts gave them. It’s generally a good thing to take what the puzzle gives you.

For those who are just tuning in, this is one of a series of posts where I show how long it takes for me to do a Sudoku puzzle with the additional restriction of having to fill in the numbers in top-to-bottom, left-to-right order. Hence the name TBLR Sudoku.

Here are the times from the past two weeks.

2/11/10 – 4-Star Sudoku in the Star-Tribune, done filling in the numbers top-to-bottom, left-to-right, in 46:06, nowhere near my personal best, but any completion is good.
2/10/10 – 3-Star, Fail. I got some numbers switched around in my mind.
2/09/10 – 2-Star, 35:29
2/08/10 – 1-Star, 26:07
2/07/10 – Didn’t do the puzzle, was preoccupied with the Super Bowl
2/06/10 – 6-Star, completed the puzzle but didn’t time it. It just didn’t seem right to tell a hungry child “Can’t you see I’m working on this puzzle, and timing it?”
2/05/10 – 5-Star, Fail. It had something to do with getting alternative possibilities mixed up in my head.
2/04/10 – 4-Star, Fail. My previous fail before this one was on January 15, so I had a nice run of puzzle success.
2/03/10 – 3-Star, 1:09:20. At many times the opportunity to just make a choice and see if it works presented itself, but I resisted temptation.
2/02/10 – 2-Star, 29:57
2/01/10 – Didn’t do the puzzle, not really sure why. I believe I did it, but somehow didn’t record my time.
1/31/10 – 5-Star, 57:21
1/30/10 – 6-Star, 1:05:00
1/29/10 – 5-Star, 51:50

There were no new personal bests this week, so the personal bests are unchanged from the last post.

1-Star: 18:13, 11/23/09
2-Star: 20:24, 1/12/10
3-Star: 31:46, 1/20/10
4-Star: 33:37, 1/28/10
5-Star: 39:58, 12/11/09
6-Star: 53:38, 1/23/10

I’m hoping that someone will read these posts, and realize that I’m occasionally capable of a certain degree of concentration.

Technorati: Sudoku

Timing TBLR Sudoku, 1/15/2010 – 1/28/2010

It seems to be working out to write one of these posts every two weeks, instead of once a week as originally planned.

For those who are just tuning in, this is one of a series of posts where I show how long it takes for me to do a Sudoku puzzle with the additional restriction of having to fill in the numbers in top-to-bottom, left-to-right order. Hence the name TBLR Sudoku.

My strategy has given higher priority to looking for six numbers in every row, column and 3 x 3 box before I start my regular scan. Furthermore, whenever I get six numbers in a row, column, or 3 x 3 box, I interrupt my scan and see if I can finish that row, column or box. If I can’t, then it’s a sign I need to do more scanning.

Here are the times from the last two weeks:

1/28/10 – 4-Star Sudoku in the Star-Tribune, done filling in the numbers top-to-bottom, left-to-right, in 33:47, a new personal best for a 4-Star, an improvement of almost 5 minutes on the previous personal best.
1/27/10 – 3-Star, 41:25
1/26/10 – 2-Star, 27:19
1/25/10 – 1-Star, I was interrupted by some friends, and I didn’t want to say “Can’t you see I’m doing a puzzle?!?” No time recorded for this day.
1/24/10 – Didn’t do the puzzle
1/23/10 – 6-Star, 53:38, a new personal best for a 6-Star, an improvement of over 8 minutes on the previous personal best
1/22/10 – 5-Star, 40:08
1/21/10 – 4-Star, 1:00:44
1/20/10 – 3-Star, 31:46, a new personal best for a 3-Star, an improvement of almost 10 minutes on the previous personal best
1/19/10 – 2-Star, 26:34
1/18/10 – 1-Star, 26:48
1/17/10 – Didn’t do the puzzle
1/16/10 – Didn’t do the puzzle
1/15/10 – 5-Star, Fail after 90 minutes

The personal bests are as follows:

1-Star: 18:13, 11/23/09
2-Star: 20:24, 1/12/10
3-Star: 31:46, 1/20/10
4-Star: 33:37, 1/28/10
5-Star: 39:58, 12/11/09
6-Star: 53:38, 1/23/10

The interesting thing about doing these puzzles this way is learning how to not suffer when I don’t have enough information to fill in a square, to realize I need to just keep looking.

Technorati: Sudoku

Timing TBLR Sudoku, 1/1/10 – 1/14/10

I’m noticing that as I do more Sudoku puzzles, I’m developing a greater ability to know what three numbers are missing, when given a sequence of six numbers. For example, if I look at 2 8 4 6 9 5, I can quickly see that 1 3 7 is what’s missing. At this point, you are supposed to say “You have a lot of time on your hands, don’t you?”

Here are the times for the last two weeks

1/14/10 – I solved the 4-star Sudoku in the Star-Tribune, top to bottom and left to right (TBLR), but as I started to do the puzzle, I realized I had not put on my watch that morning, and so was unable to time it.
1/13/10 – 3-star, 41 minutes and 6 seconds. New personal best for a 3-star
1/12/10 – 2-star, 20:24. New personal best for a 2-star
1/11/10 – 1-star, 25:15. My best recorded time on a 1-star is 18:13
1/10/10 – Didn’t do the puzzle
1/09/10 – 6-star, 1:04:00. First time ever to solve a 6-star TBLR, a new personal best
1/08/10 – 5-star, TBLR Fail. I then tried doing it the normal way, and Failed again.
1/07/10 – 4-star, 57:36. My best recorded time on a 4-star is 38:31
1/06/10 – 3-star, TBLR Fail. I did the puzzle successfully the regular way.
1/05/10 – 2-star, 27:27 First time to solve a 2-star TBLR, a new personal best
1/04/10 – 1-star, TBLR Fail. I got impatient and made a guess, which turned out to be wrong
1/03/10 – Didn’t do the puzzle
1/02/10 – Didn’t do the puzzle
1/01/10 – 5-star, 47:32. My best recorded time on a 5-star is 39:58

I’d like to think I’m getting better at this, but I’m not really what the point is, besides being more focused in using my imagination.

Technorati: Sudoku

Timing TBLR Sudoku, Since The Last Post, Whenever That Was

So much for doing one post each week showing my TBLR (Top-to-Bottom, Left-to-Right) Sudoku times. But I will give you the last week-or-so’s worth of times.

12/31/09 – 4-Star Sudoku, (Star-Tribune) 38:31
12/30/09 – 3-Star Sudoku, 50:31. Don’t really know why it took so long.
12/29/09 – Silver Janrick Sudoku (Pioneer-Press) 28:27. I did the Janrick Sudoku in the Pioneer-Press because I stupidly put 50 cents in the Star-Tribune news rack in front of the Ford Parkway Bakers Square, only to discover that it was sold out. I was clearly not paying attention.
12/28/09 – Bronze Janrick Sudoku 16:something-something. I did the Janrick Sudoku because I did the 2-star Sudoku with the gentleman in Lund’s who does the Sudoku puzzles entirely in his mind. We didn’t do this one in our minds.
12/25/09 – 5-Star Sudoku, Fail.
12/24/09 – 4-Star Sudoku, Fail.

Technorati: Sudoku

Cylindrical Sudoku 1

I’ve been threatening to do this for some time, and I finally got around to it. Here’s how it works.

This isn’t exactly a cylinder; it’s a regular nonagonal prism. That means the cross section is a regular nonagon, a nine sided polygon with equal sides and equal angles. The above picture shows 5 of the 9 columns. The other 4 are on the other side of the prism, hidden from view.

“How can I possibly solve the puzzle when I can’t see four of the columns?”

Here are the other four columns, the other side of the prism.

“Why is the prism colored red, green and blue?”

If the prism was colored white and gray like a normal Sudoku grid, then there would be two gray 3 X 3 boxes touching each other, or two white 3 X 3 boxes touching each other, and that wouldn’t look pretty.

“Why is the back different from the front?”

Because nine is an odd number, and if I’m going to show all the columns, one side has to have 5 columns, and the other side has to have four.

“Why are some of the columns horizontally squished?”

The only column that you see straight on (perpendicular to your line of sight) is the center column of the front view. All the other columns appear to be squished because they are slanted away from you, some of them a little bit, some of them a lot.

Other than that, it’s a normal Sudoku puzzle. Fill in the grid with the numbers 1 through nine so that there is no duplication in a row, column or 3 X 3 box. You can tell what’s coming next, can’t you? Yes, cylindrical Sudoku in Chinese!

Technorati: Sudoku

A Cypriot Syllabary Sudoku

The Cypriot syllabary is a syllabic script used in Iron Age Cyprus, from ca. the 11th to the 4th centuries BCE, when it was replaced by the Greek alphabet. But it seems to have enough interest to have its own Unicode chart

Here is the solution to the Coptic Sudoku of Nobember 25

Rethinking Timing TBLR Sudoku

Somehow, in the course of seeing if I could solve Sudoku puzzles top-to-bottom, left-to-right (TBLR) in 30 minutes or less, I stopped having fun. So instead of seeing what percentage of the time I could solve a puzzle TBLR in under 30 minutes, I’ve decided to just do the puzzles and see how much time it takes, and see if I can improve my time. The not being under time pressure seems to help. I will keep doing one post a week, unless, of course, I stop having fun doing it this way.

Thursday, 12/10/09: 4-star, 45:00
Friday, 12/11/09: 5-star, 39:58
Saturday, 12/12/09: 6-star. I got tired around 40 minutes and I made a choice without following the consequences far enough. Fail.

A Somewhat Coptic Sudoku

When I created this puzzle, I asked for two random numbers between 1 and 9, and received 9 and 8, again not the random numbers I wanted.

The last time I did this, I never got around to actually solving the puzzles I created. I have done so this time. Here is the solution to the Slightly Armenian Sudoku from November 12. The little numbers in the top right corner of some of the squares signify the order in which I filled up the grid.

On further review, the character I used came from the Armenian ligature Unicode set. In this context, ligatures are characters which stand for multiple characters. I was confused by the Unicode website. I got the impression that the Armenian ligatures set was the main Armenian character set, but it isn’t. I shall have to make another Armenian Sudoku eventually. I didn’t know what to call this Armenian ligature when I was solving the puzzle. But it reminded me of a Hebrew letter, so I called it “Gimel.” I later discovered that there isn’t a Hebrew letter that looks like this symbol. Since there were no 2’s given in this puzzle, I could have decided that Gimel stood for 2 instead of 1. But when I was composing the puzzle, and I asked for a random number between 1 and 9, I received the number 1. So Gimel stands for 1. Got that?

One thing I notice is that to solve these puzzles with unusual symbols, I have to make the unusual symbols part of an ordering of all the symbols. In this case, my ordering was “Gimel-2-3-4-5-6-7-8-9.” Will this Coptic puzzle be significantly harder than the Armenian one? We’ll find out soon enough!

Timing TBLR Sudoku, 11/17/09-11/23/09

Today was a really bad day for TBLR Sudoku. I had the incredibly fast time from last Tuesday staring over my shoulder, and I ended up imagining the incorrect number in a square, which lead to the inevitable TBLR fail. I got another copy of the Variety section that was laying around, and started doing the puzzle the regular way. I imagined something that wasn’t there then too, and I failed on a 2-star, which is pretty rare for me. I copied the puzzle onto a piece of paper and tried again, finally succeeding. Sounds like Swamp Castle (“Ah, but the fourth castle, it stayed up!”). I am therefore 1 out of 2 in solving 2-star puzzles TBLR in 30 minutes.

Wednesday, 11/18/09: 3-star. I did the puzzle, but didn’t record what I’ve usually been recording. I therefore count myself as 0 for 2 in solving 3-stars (by “solving” I mean “solving TBLR in 30 minutes”)
Thursday, 11/19/09: 4-star, 56 open squares, 0 filled, 31 identified in 30 minutes. That’s a new personal best on the number of squares identified in a 4-star. I filled in the squares I identified, and took an additional 3:03 to finish the puzzle. 0 for 2 in solving 4-stars.
Friday, 11/20/09: 5-star. I didn’t count the squares because I failed in both the TBLR solving and the solving of any kind. 0 for 3 in solving 5-stars
Saturday, 11/21/09: 6-star. I did the puzzle, but didn’t try to do it TBLR.
Sunday, 11/22/09: Didn’t do the puzzle.
Monday, 11/23/09: 1-star, 56 open squares, 56 filled in 18:13. New personal best, making up for the lousiness of earlier in the week. 1 for 2 in solving 1-stars.