?

Log in

No account? Create an account

Previous Entry | Next Entry

HELP!: Sudoku

My mother-in-law brought this one to me, directly from the LA Times, becasue she couldn't solve it without taking a guess. And it's only rated Tough...


The original puzzle is this:

x x x | x x 7 | x 6 x
x x x | 4 x x | x x 1
x x 2 | 5 x x | 3 x x
------+-------+------
x 6 9 | 7 x x | 4 3 x
4 x x | 1 x 6 | x x 8
x 5 7 | x x 9 | 1 2 x
------+-------+------
x x 5 | x x 3 | 8 x x
2 x x | x x 4 | x x x
x 8 x | 9 x x | x x x


Obviously, the x's are where there are spaces. Both she and I hacked away at this thing to get to this point:

x x x | x x 7 | x 6 x
x x x | 4 x x | x x 1
x x 2 | 5 x 1 | 3 8 x
------+-------+------
1 6 9 | 7 x x | 4 3 5
4 2 3 | 1 5 6 | x x 8
8 5 7 | 3 4 9 | 1 2 6
------+-------+------
x x 5 | x x 3 | 8 x x
2 x x | x x 4 | x x x
x 8 x | 9 x 5 | x x x


Thing is... what's next? I can't see a logical place to go from here. There are too many number sets and whatnot. I could just put in a number and see what happens, but I've never had to do that before. I've always found a way to logically ascertain where the numbers go.

Any suggestions? I just need the next step and not the finished puzzle.


We now return you to your friends list, already in progress.

Tags:

Comments

( 16 comments — Leave a comment )
hmtriplecrown
Nov. 6th, 2005 07:40 pm (UTC)
Try this...

x x x | b a 7 | x 6 x
x x x | 4 a b | x x 1
x x 2 | 5 a 1 | 3 8 x
------+-------+------
1 6 9 | 7 b b | 4 3 5
4 2 3 | 1 5 6 | x x 8
8 5 7 | 3 4 9 | 1 2 6
------+-------+------
x x 5 | x x 3 | 8 x x
2 x x | c x 4 | x x x
x 8 x | 9 x 5 | x x x


a = location of one of the following: 369
b = location of one of the following: 28
c = 8

Try putting an 8 in the location of the c (bottom center 3x3 grid), center left slot). You can't put a 2 there, due to the 2 in that row.
rialtus
Nov. 6th, 2005 07:48 pm (UTC)
Ah, but here's the rub (unless I'm missing something). I agree with you that row 1, coulmn 4 is either a 2 or 8, but row 7, column 4 could be either 2 or 6, and row 8 column 4 could be either 6 or 8.

(And yes, your icon is entirely appropriate!)
hmtriplecrown
Nov. 6th, 2005 07:57 pm (UTC)
You noticed the icon? I'm honored. :-) Back to the puzzle at hand...

Shoot, you are right. Back to the drawing board or a sudoku puzzle solver...
rialtus
Nov. 6th, 2005 08:26 pm (UTC)
Hm... problem solver... tried this one and it came down to the same exact numbers I did, with the exact same possiblities that I did.

I beginning to think the LA Times did a misprint.
hmtriplecrown
Nov. 6th, 2005 08:33 pm (UTC)
I GOT IT!
I have the solution in my hands. I took a very educated guess on one square. After filling it in, everything fell into place.

If you want to know the location and the number of this educated guess, let me know.
rialtus
Nov. 6th, 2005 08:57 pm (UTC)
Re: I GOT IT!
Ah, but see, ya had to guess, which is what I was trying to avoid myself.

So which square? Let's see if I choose the same number as you do...
hmtriplecrown
Nov. 6th, 2005 09:01 pm (UTC)
Re: I GOT IT!
The square is the top right hand square of the entire puzzle--top right 3x3 grid, top right square.

I tried doing the puzzle without guessing but got as far as you two.
rialtus
Nov. 6th, 2005 09:17 pm (UTC)
Okay...
That's row 1 column 9... possibilties are 2, 4, and 9.

See, I would have figured you to go to row 8, column 4 with the 6 and 8 possibility still, just because it's only two numbers to directly address, and it quickly completes that column and and the middle 3x3 grid. I actually went with your suggestion from above and put an 8 there, and it all fell in.

Either way, bad on the LA Times for making us guess.
hmtriplecrown
Nov. 6th, 2005 09:24 pm (UTC)
Re: Okay...
I was thinking about picking from the 6 and the 8. I don't know why I picked this number in the top right corner besides an educated guess, but it worked.

In the end, someone dropped the ball at the Times. There would have been no problems solving the puzzle if you were given that upper right #.

*rereads your above comment*

Wait, you picked the 8? I put the 4 in the upper right corner, and everything fell into place. :-P It's possible that there are multiple solutions if the Times did a booboo by omitting a number...
hmtriplecrown
Nov. 6th, 2005 09:28 pm (UTC)
My solution
3 1 8 | 2 9 7 | 5 6 4
5 7 6 | 4 3 8 | 2 9 1
9 4 2 | 5 6 1 | 3 8 7
------+-------+------
1 6 9 | 7 8 2 | 4 3 5
4 2 3 | 1 5 6 | 9 7 8
8 5 7 | 3 4 9 | 1 2 6
------+-------+------
7 9 5 | 6 1 3 | 8 4 2
2 3 1 | 8 7 4 | 6 5 9
6 8 4 | 9 2 5 | 7 1 3
rialtus
Nov. 6th, 2005 11:37 pm (UTC)
*ding*
Yup, the same one I got. I tried doing the same with the 6 and got duplicate numbers all over the place.
msmcfeeley
Nov. 6th, 2005 08:12 pm (UTC)
This kind of puzzle makes my head spin.
*back to watching porn*
rialtus
Nov. 6th, 2005 08:26 pm (UTC)
So I take it you won't be turning into Linda Blair any time soon, huh?
msmcfeeley
Nov. 6th, 2005 08:42 pm (UTC)
no, gracias
mefailenglish
Nov. 7th, 2005 02:15 am (UTC)
OK, I hacked at this and got nowhere. Then I plugged it into this Sudoku solver and it made a couple more eliminations when it finally came back: "Could not solve by steps. Need to guess a cell".

Seems like they left out a number when they misprinted, or there was an error in setting?
rialtus
Nov. 7th, 2005 06:28 am (UTC)
With pretty much every automated system and now four people having issue, I'd have to say that something was amiss. It's definitely a puzzle that they shouldn't have printed. Having to guess ain't the Sudoku way.
( 16 comments — Leave a comment )