Remember that lame-ass math puzzle thread? [Archive]

-N-

10-15-2005, 10:59 PM

The rules of Sudoku are simple. Enter digits from 1 to 9 into the blank spaces. Every row must contain one of each digit. So must every column, as must every 3x3 square.

Each Sudoku has a unique solution that can be reached logically without guessing.

nik0tine

10-15-2005, 11:00 PM

Jesus Christ I've already quit.

Luara

10-15-2005, 11:03 PM

LOL

rubah

10-15-2005, 11:17 PM

That's easier than the last one I tried, neel, It hink.

Congratulations! You solved the Sudoku in 14 minutes, 34 seconds!

and when I'm not distracted by IRC

Congratulations! You solved the Sudoku in 9 minutes, 45 seconds!

radyk05

10-16-2005, 01:45 AM

now i have something to do in the internet...

eestlinc

10-16-2005, 02:43 AM

those are kind of fun.

Necronopticous

10-16-2005, 02:56 AM

I WIN. Fun stuff.

Rye

10-16-2005, 02:57 AM

Jesus Christ I've already quit.

Doomie

10-16-2005, 03:10 AM

SUDOKU with Coldplay:

Congratulations! You solved the Sudoku in 11 minutes, 40 seconds!

ff7+ff10 gurl 100

10-16-2005, 03:24 AM

I still dont get it

rubah

10-16-2005, 03:41 AM

It's easy.

You have to use each number 1-9 in every row, column, and square. You cannot use them twice.

Awrini

10-16-2005, 06:57 AM

12min 27 sec. I suck.

Awrini

10-16-2005, 07:08 AM

Second attempt 9min 59 sec, 0 errors.

DOH EDIT BUTTON!

Meat Puppet

10-16-2005, 07:52 AM

i like sudoku but I fail under pressure
and someone told me I was pretending to be asian and I said no I am not pretend ing to be asian at all and then he
grabbed the outter corners of each eyes and pulled and stretched downwards to give himself squinty eyes and because the ones that go down are japanesese and the ones that go up are chinese or sometimes taiwanese and he made funny noises with his mouth and we had a fight

Tasura

10-16-2005, 09:39 AM

9 minutes, 18 seconds at 5:40am watching Casino/Good Fellows.

Miriel

10-16-2005, 10:23 AM

Congratulations! You solved the Sudoku in 8 minutes, 3 seconds!

Lame.

Dignified Pauper

10-16-2005, 10:49 AM

I beat Rube by one second.

Congratulations! You solved the Sudoku in 9 minutes, 44 seconds!

Endless

10-16-2005, 11:27 AM

If I do it by hand:
Congratulations! You solved the Sudoku in 7 minutes, 22 seconds!

If I cheat with my calc :p:
Congratulations! You solved the Sudoku in 3 minutes, 16 seconds!

Captain Maxx Power

10-16-2005, 12:43 PM

Sudoku! I love you Neel :love:

Dr Unne

10-16-2005, 06:00 PM

That site you linked to gives broken puzzles. More than one solution is sometimes possible, but it only accepts one of them as the proper solution. See attachments. Easy puzzle 3,077,057,385.

Spatvark

10-16-2005, 06:12 PM

the second one there isn't valid Unne; you can't have the same number twice in one of the nine 3x3 squares

Resha

10-16-2005, 06:17 PM

I love Sudoku. Really fun stuff! :D And actually, once you figure out the method, it's pretty easy, depending on how many numbers they give you. The less you get, the harder it is, but the basic strategy applies throughout.

Dr Unne

10-16-2005, 06:20 PM

the second one there isn't valid Unne; you can't have the same number twice in one of the nine 3x3 squares

Ah, it probably helps if you read the directions, huh. That sure makes it easier to solve too.

Laugh at face of Danger

10-16-2005, 06:22 PM

*makes cross with fingers*

*hisses*

NOT THE EVIL SODOKUS!

*runs*

-N-

10-17-2005, 10:17 AM

My best time on easy was 7 min 12 secs - the only time I was better than average. I consistently get around 8-9 mins.

My best time on medium was an appalling 20 minutes, even when using the most robust method (mark every possibility for every value, then eliminate based on logic). It could be because I'm tired and sleepy, though.

My suitemate is our class's top math major - he does "evil" for fun.

My roommate is a CS major who is trying to write a solver.

This game is too addicting. :D

Shoden

10-17-2005, 04:04 PM

I like Sudoku But I take a while at it, 13 mins.

Dr Unne

10-17-2005, 11:48 PM

My best is 3 minutes 11 seconds for an easy one. Clearly my sudoku-penis is bigger than all of yours; however my reading-the-directions-penis is small and insignificant, so they kind of cancel each other out. :( And now I'm going to have to write a solver too.

Shoden

10-17-2005, 11:53 PM

What a way to put it XD.

I'm kinda slow at this stuff but I can do them.

rubah

10-18-2005, 12:10 AM

I think they have pills for that stuff, Unne.

Dr Unne

10-18-2005, 02:20 AM

My Sudoku solver: http://chwombat.net/perl-sudoku.php (obviously in Perl). I just wasted two and a half hours on it. They probably have pills for that, too.

Del Murder

10-18-2005, 05:59 AM

I do these at work sometimes when it gets slow. They're fun.

Tasura

10-18-2005, 06:23 AM

I bought a book of them after thanksgiving so id have something to do at university.

Del Murder

10-19-2005, 03:13 AM

The problem with these is that they get boring after a while since it's pretty much the same thing over and over again.

-N-

10-19-2005, 09:10 PM

Then try and time yourself. :D

Shoden

10-19-2005, 11:01 PM

Took me 15 mins on my 2nd try. Gah

Del Murder

10-20-2005, 02:45 AM

I will if I get bored. Here's some questions:

1. How many unique 9X9 Sudoku squares are there?

2. What is the minimum number of numbers you need to have to make a unique 9X9 Sudoku square?

Optium

10-20-2005, 02:48 AM

Ya, this game is pretty awesome. Not very mathy though. :o

9 minutes on the hardest level was my best time I think, but I was talking
to a friend online at the time, I should try again without any distractions.

.opt

Dr Unne

10-20-2005, 05:13 AM

So you can get less than half the average time, while distracted. How? How long have you been playing?

Optium

10-20-2005, 09:23 PM

So you can get less than half the average time, while distracted. How? How long have you been playing?
Yes. And about a total of an hour. I did evil after playing the easy one 3
times. It was all in the same sitting. It was last Friday. Just played Evil
again without any real distractions unless you count parents, music, and
making food, but I wasn't actually IMing someone, and I noticed the pause
button this time so I paused it to stir/drain/eat my pasta.

.opt

-N-

10-20-2005, 10:02 PM

That's obscene. I'm still proud of my 8'36" medium. I'll work my way up eventually. :D

Murder - I assume you're talking about creating Sudoku puzzles. I don't know exactly, but I think this quote from Wikipedia might help.

If an efficient solver is available, there is a very simple method of automatic construction: randomly add a digit to the grid, and then look for a solution. If no solution is found, remove the digit and try another. If a solution is found, look for a different solution. If there is no other solution, the starting grid is complete; otherwise, repeat this process.

edit: Hooray 4'28" on easy time for class now.

Endless

10-20-2005, 10:36 PM

The question is, was that grid valid at all times or did you use trial and error?

A very, very easy way to generate a valid sudoku (filled grid) is:
<pre>
a b c d e f g h i
g h i a b c d e f
d e f g h i a b c
i a b c d e f g h
f g h i a b c d e
c d e f g h i a b
h i a b c d e f g
e f g h i a b c d
b c d e f g h i a
</pre>

Tasura

10-21-2005, 02:31 AM

i got bored in calc so i made 3 i think that work.

Dr Unne

10-21-2005, 10:42 PM

Yes. And about a total of an hour. I did evil after playing the easy one 3
times. It was all in the same sitting. It was last Friday. Just played Evil
again without any real distractions unless you count parents, music, and
making food, but I wasn't actually IMing someone, and I noticed the pause
button this time so I paused it to stir/drain/eat my pasta.

.opt

You didn't answer "how".

Old Manus

10-21-2005, 10:48 PM

Congratulations! You solved the Sudoku in 23 seconds! You 1337 h4xx0r!

Del Murder

10-22-2005, 02:05 AM

No, I'm not trying to create them. I'm just curious as to how many possible combinations there are, and how many numbers one needs to be unique. I started trying to compute the first one, and got through the first few squares, but once you try finding the combinations for the middle squares it gets tricky.

For example, for the upper leftmost square, there are 9 (1-9) different numbers you can put there. Then for the square to its right there are 8 possible numbers, since you can't use the first number again. You can go on down the line to find that there are 9! ways to fill the first row. Then, for the second row there are 6 ways to fill the first square, since it shares a 3X3 box with the three numbers above it, and you can't use any of those. So now you have 9!*6 ways to fill 1 row and 1 square in the next row. And so on...

Spammerman

10-22-2005, 02:10 AM

Congratulations, U have shot the guy who posted sudoku on the web in .32 seeconds.

Endless

10-22-2005, 01:43 PM

No, I'm not trying to create them. I'm just curious as to how many possible combinations there are, and how many numbers one needs to be unique.

According to Bertram Felgenhauer, there are 6,670,903,752,021,072,936,960 possible valid 3x3x3 sudoku grids, which falls to 5,472,730,538 when symmetries are taken into account.

And the lowest number of hints known as of now that leads to a unique solution is 17.

-N-

10-26-2005, 07:51 AM

WHOOOOOOOOOOOOOOO

rubah

10-26-2005, 11:55 PM

update your firefox neel.

And that was three minutes you could've been on irc!

Xaven

10-27-2005, 12:50 AM

I finished easy in 30:27. Darn. (first try)

raskerino

10-27-2005, 02:57 AM

4:14 seconds on easy, I don't have much skill though I restart 'til it works with my specifically bad method of doing these (in other words any medium would take me an hour).

Lindy

10-27-2005, 03:19 AM

"Remember that lame-ass math puzzle thread?"

Yeah, but Sudoku isn't maths, it's just number positioning.

I think it's Japanese for "Haha stupid westerners waste time on puzzles while we further our advanced technology".

Or something like that anyway.

Probably without the R's.

Del Murder

10-27-2005, 04:25 AM

What have you furthered, Lindy?

Lindy

10-27-2005, 12:20 PM

Myself actually, in the time I see other people doing Sudoku puzzles on the train when I'm going to Uni, I'm doing Biology/Chemistry/Biochemistry work for my Degree course.