Sudoku anyone?

Feel free to post anything unrelated to wet shaving or men's grooming (I.e. cars, watches, pens, leather goods. You know, the finer things of life).
Post Reply
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Sudoku anyone?

Post by brothers »

I'm just a beginner but I've begun to enjoy it. Does anyone have some tips that might make it somewhat easier for a rookie to understand? I do understand the objective of the game, but it seems to be much more challenging than it was at first glance.
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
User avatar
rustyblade
Shaving Paparazzo
Posts: 10472
Joined: Sun Oct 23, 2005 5:27 pm
Location: Ontario

Re: Sudoku anyone?

Post by rustyblade »

This is a game I really want to understand the advanced concepts to learn how to solve difficult puzzles, but it sadly makes me realize that I don’t math well. :(
Richard
Gene
Posts: 1508
Joined: Fri Mar 14, 2008 11:58 am
Location: Buda, TX

Re: Sudoku anyone?

Post by Gene »

I like working the puzzles a lot. I found a couple of apps - and I do the easy ones when I want to let my mind wander. The medium's and hard's require me to put little number in the boxes too much (if you do these you understand that).

I find that often times what does NOT go in the box is as important to know as what does go in the box.
Gene

"It could probably be shown by facts and figures that there is no distinctly American criminal class except Congress."
Mark Twain

"People shouldn't be afraid of their government. Governments should be afraid of their people."
Alan Moore
User avatar
John Rose
Posts: 445
Joined: Wed Aug 24, 2016 8:11 pm
Location: New Brunswick, Canada
Contact:

Re: Sudoku anyone?

Post by John Rose »

Sudoku is my 3rd favourite time-killer, after Klondike Solitaire (on my iPod) and Cryptic Crosswords (in paperback book compilations).
I think I'd rather not learn tricks to speed up the solution.
"If this isn't nice, then what is?" - Kurt Vonnegut's Uncle Alex
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

I'm beginning to "see" some options that have taken some time for my subconscious to understand. A couple of days ago I finally finished one with zero mistakes, which was a first for me. Of course I'm still limiting myself to the "easy" ones for the time being.
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
User avatar
Pauldog
Never Shave a Husky
Posts: 6313
Joined: Fri Jul 29, 2005 6:39 pm

Re: Sudoku anyone?

Post by Pauldog »

To be technical, Sudoku is math, since logic is a branch of math, but it's not quantitative. You could replace the digits with any set of 10 different symbols.

The first thing I do is fill in the easy unfilled squares, ones where it doesn't take too much effort to see there's only one choice of digit. Then I look for two squares in the same square of 9 that are the only possibilities for the same digit, or two squares in the same row or column. That eliminates that digit as a possibility in the rest of that row or column or square of 9. That often gives you some more solved single squares.

At opportune times, I see if I can use a process of elimination to fill in any single squares, mostly when a lot of the nearby squares have been filled in.

A little later, I start marking squares with all digits they might have (I write in the possible digits), looking first for squares with the least number of possibilities. The easiest puzzles have few squares with lots of possibilities.

There's more, but it's hard to write it all down without diagrams and examples. The main thing is to keep in mind that rows, columns, and squares of 9 can't have any repeating digits. Solving the puzzle is by using the consequences of that fact, and figuring out (or learning about) all the possible consequences.

More often than I'd like, I discover an impossibility, which means that I made a mistake. Those have been nearly impossible to repair without erasing all my work.
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

I've been playing Sudoku for almost 6 months now. I have been depending on my subconscious to begin to figure out what and where to look for the correct results. Identifying the digits and their positions in the overall scheme is the most difficult thing. Training my brain would be a good way to describe it. Pauldog has stated the process very well. I don't know if it's mathematics or just any series of 9, be it alphabet, symbols, or etc. just so the 9 digits are always in place. The big secret that I have learned is that 100% of mistakes are absolutely foreseeable. If I take all the time in the world as I look at the numbers and their positions and relationships, the fact remains that mistakes are absolutely avoidable. Taking a wild guess is tempting, but completely avoidable. This is a game winnable every time if there's no rush. Sometimes I have to pause and get back to it later. What appears to be impossible is entirely avoidable.
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
User avatar
Pauldog
Never Shave a Husky
Posts: 6313
Joined: Fri Jul 29, 2005 6:39 pm

Re: Sudoku anyone?

Post by Pauldog »

On rare occasions I'll do one that's so hard that there doesn't seem to be any way to go forward at a certain point except to guess a square that has two possibilities. I need to mark every square thereafter so I can erase it if I get a contradiction. If that happens, then I change the first square to the other possibility.

That's the only time I guess.
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

Pauldog, I agree. Often I find myself at what appears to be a dead end with no way out, and after staring at the board or even intentionally distracting myself for a few minutes it seems that my subconscious brain kicks in with a suggestion that opens up a solution. I really don't allow myself to guess because that's almost always wrong in my case.
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
User avatar
John Bader
Posts: 2
Joined: Sun Nov 22, 2020 3:38 pm

Re: Sudoku anyone?

Post by John Bader »

When I was at hospital I met one man who was mad about sudoku. He explained to me the rules and lately I found out how useful the game was for the brain. Since then I try to play sudoku at least once a week to train my brain to be better at WoW, my current gaming fav :) if that doesn't help then I go to https://skycoach.gg/wow-boost/dungeons and ask pro gamers for their assistance!
Last edited by John Bader on Mon Dec 07, 2020 5:29 am, edited 1 time in total.
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

My own shortest record time to a solution with zero mistakes is a little over 12 minutes, and usually much longer. The website I see tells me that about 95% of everyone else solves theirs much faster (with zero mistakes) than I do. I just can't even imagine someone solving one of the puzzles with no mistakes that often and that fast. :shock: There's got to be something I've been overlooking. But I'll either figure it out or get disgusted and quit. :wink:
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

Overnight my subconscious must have figured something out. It got easier to spot where to put the missing numbers. Maybe this will help speed things up. I understand a lot of folks write possible numbers in the boxes, but I am striving to be able to solve the puzzle without any errors which in my case are just guesses, almost always wrong.
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

It took me 10 months to discover why everyone on that website can solve every puzzle, no matter how difficult, in record time. There is a pause button and there is also a print button. What those folks do is simple: Go to the website and log on to a new puzzle, immediately push print and immediately after that, push pause. Take as long as you want to solve the puzzle the old fashioned way, then un-pause the puzzle long enough to fill in the solution and hit the finish button. I knew there was something fishy going on! They all cheat. :evil:

14January2021 Edit: Yesterday I tested my hypothesis about cheating the crowd. Success! :D And it made me laugh out loud. It normally takes me anywhere from about 20 minutes up to 35 minutes or longer to solve the puzzle. Considering the fact that the puzzle was paused except long enough for me to print the puzzle and then un-pause it just long enough for me to type in my results, according to the dumb website, it took me only 2 minutes and 22 seconds, and it was hilarious. Only 6% of those who've solved this particular puzzle over the years, even with the cheating, were faster than me. Of course it really took me around 30 minutes to solve the puzzle in real time as opposed to fake time. I get no satisfaction from lying to an automated and obsequious digital robot. It gives me no satisfaction lying to anyone, ever, of course. I think I will continue to get my puzzles by printing them off at random, and solving them at my own pace with no incentive to report my results to the robot. :roll:
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

After I figured out how to play and win every time, I've lost interest. Not totally, but as with most other games, I get little or no satisfaction from playing against myself and "winning". I already know I'm a winner! 8)
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
User avatar
Sam
M'Learned Friend
Posts: 12017
Joined: Thu Jul 29, 2004 9:13 am
Location: memphis, tennessee
Contact:

Re: Sudoku anyone?

Post by Sam »

I got hooked onto Crosswords while waiting in a bankruptcy trustee's meeting for hours. Someone handed out the USA Puzzle and pencils and well, I took the bait. Now I have the app on my computer and do it every day, even if out of town (and I get antsy enough that I bring my IPad on vacation and make sure I get the hotel wifi password). NY Times Sunday edition is a killer and I try my hand every now and then, but even though friends think I am a fount of trivia and knowledge, the NYT Sunday edition is more like advanced Jeopardy and, well, I know my limits. Fun to see if I get more than half of them
scruffy
Posts: 453
Joined: Wed May 02, 2007 11:24 am
Location: New York, NY

Re: Sudoku anyone?

Post by scruffy »

I have discovered a number of tricks. You can do the numbers in sequence doing three grids at a time. For instance if #1 goes in the first row of the first grid, than it also goes in the second or third row of the second grid, and the remaining row of the third grid. Do the same thing for the #2, etc. One row and one column can also be done making sure that the numbers 1 through 9 do not get repeated in the row or columm. I hope it makes sense the way I explained it.
Ed
brothers
Posts: 21513
Joined: Sun Sep 14, 2008 7:18 am
Location: Oklahoma City USA

Re: Sudoku anyone?

Post by brothers »

scruffy wrote: Thu Apr 22, 2021 1:02 pm I have discovered a number of tricks. You can do the numbers in sequence doing three grids at a time. For instance if #1 goes in the first row of the first grid, than it also goes in the second or third row of the second grid, and the remaining row of the third grid. Do the same thing for the #2, etc. One row and one column can also be done making sure that the numbers 1 through 9 do not get repeated in the row or columm. I hope it makes sense the way I explained it.
I'll try to remember to try these strategies next time I play it.
Gary

SOTD 99%: Monday, Wednesday, and Friday, soaps & creams, synthetic / badger brushes, Colonial General razor, Kai & Schick blades, straight razors any time, Superior 70 aftershave splash + menthol + 444
Gene
Posts: 1508
Joined: Fri Mar 14, 2008 11:58 am
Location: Buda, TX

Re: Sudoku anyone?

Post by Gene »

Another trick:

Take the top row - the numbers will be from 1 to 9. If the number 1 is missing - first look at the 3x3 top squares - if the number 1 is in them that eliminates it from your search. For any where there is no number 1 - look at the columns underneath the blanks - if a number 1 is in that column then it is off the list. With luck you will identify a blank that can only be the number 1. Sudoku is sometimes a puzzle of elimination, too. Hope that makes sense?
Gene

"It could probably be shown by facts and figures that there is no distinctly American criminal class except Congress."
Mark Twain

"People shouldn't be afraid of their government. Governments should be afraid of their people."
Alan Moore
User avatar
John Rose
Posts: 445
Joined: Wed Aug 24, 2016 8:11 pm
Location: New Brunswick, Canada
Contact:

Re: Sudoku anyone?

Post by John Rose »

The Sudoku app that I use, named "SUDOKU:)" for iOS, has the feature where you can temporarily highlight all instances of a selected number in green. This makes it easy to spot patterns. I find that just as useful as the "pencil mode" (where you can enter multiple small candidate numbers in a single square).
Also, the pencil mode automatically deletes candidate numbers after you enter one of them in the normal mode.
"If this isn't nice, then what is?" - Kurt Vonnegut's Uncle Alex
User avatar
John Rose
Posts: 445
Joined: Wed Aug 24, 2016 8:11 pm
Location: New Brunswick, Canada
Contact:

Re: Sudoku anyone?

Post by John Rose »

Here's a fun variation on a crossword puzzle: https://simplydailypuzzles.com/daily-codeword/
They give you a partially filled-out crossword puzzle, but no clues, and no way to check whether the letters are correct as you go. Once you type in a letter (right or wrong), it automatically fills it out in all places where whatever letter is supposed to go there occurs. It starts out slow, then gets easier.

There is some sort of bug in that sometimes it does not tell you when you have successfully completed the puzzle, but you can usually tell that you got it right.
"If this isn't nice, then what is?" - Kurt Vonnegut's Uncle Alex
Post Reply