Daily Hanidoku Puzzle

Interesting puzzles can be posted here
Post Reply
nj3h
Gold Member
Gold Member
Posts: 111
Joined: Mon Jul 10, 2006 12:58 pm
Location: Virginia / USA

Daily Hanidoku Puzzle

Post by nj3h »

The puzzle posted for July 19, is not symmetrical like the other puzzles posted. The 6 in the lower right corner isn't needed.

I put the puzzle into HaniCue with and without the 6. I get the same solution either way.

I presume, that without the 6 still yields a solution one can solve by logic and not by guesswork.

HaniCue is a fun variant. If you haven't tried it yet, give it a go.

Regards,
George
nj3h
Gold Member
Gold Member
Posts: 111
Joined: Mon Jul 10, 2006 12:58 pm
Location: Virginia / USA

Post by nj3h »

Upon further investigation, the 6 in the lower right hand corner does appear to be need to yield a solution that can be solved logically. My error for not checking this earlier. I just assumed that if a solution is generated, then it must have been determined through logic as opposed to some brute force approach.
Ruud
Site Owner
Site Owner
Posts: 601
Joined: Fri Dec 30, 2005 10:21 pm

Post by Ruud »

I will slowly start including a few more difficult HaniDokus, sometimes beyond the logical skills of the current HaniDoku version.

Just say "when" 8-)

Ruud
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
nj3h
Gold Member
Gold Member
Posts: 111
Joined: Mon Jul 10, 2006 12:58 pm
Location: Virginia / USA

Post by nj3h »

Ruud,
If and when you post those beyond the logical limits of HaniCue, please mention that on the daily page (perhaps along side the rating).

If the puzzles cannot be solved logically with your program, then I would assume then that guessing will be required to solve the puzzle. Personally, I am not into guessing to solve a puzzle.

What are the techniques that you have in HaniCue? Have you implemented one equivalent to forcing chains?

Anyway, that's my two cents worth.

George
Ruud
Site Owner
Site Owner
Posts: 601
Joined: Fri Dec 30, 2005 10:21 pm

Post by Ruud »

I discovered most of the techniques I describe on the website after the current release of HaniCue. It does naked & hidden singles, and keeps track of required and obsolete candidates in recognized ranges.

As a matter of fact, I discovered a new real cool trick today.

When a line of size 8 contains a cell with candidates {1,9}, these 2 candidates can be eliminated from all other cells in that line, because one of the digits must go in that bivalue cell, and the other does not fit in the 8-digit range.

I had a naked pair that could be used this way. You may encounter it in the daily puzzles later this week.

Your other remark:

I will not go as far as bifurcation or guessing. Only logic required.

Ruud
nj3h
Gold Member
Gold Member
Posts: 111
Joined: Mon Jul 10, 2006 12:58 pm
Location: Virginia / USA

Post by nj3h »

Thanks Ruud, for your answer to my comments.

I anxiously await the new release of HaniCue. Hopefully you received my email, with a Word file attachment, that provided a few suggestions/comments for the next version of HaniCue.

I presume the new version will incorporate all techniques you have come up with so far.

Thanks for all the good work you do.

George
nj3h
Gold Member
Gold Member
Posts: 111
Joined: Mon Jul 10, 2006 12:58 pm
Location: Virginia / USA

Post by nj3h »

Additional:

Ruud,

I saw a post you had on some other site about an x-wing you found in a puzzle. I hopt that will be implemented in your next version.

So, to revisit the puzzle I commented on at the top of this message thread, do you think the extra 6 is required in the lower right-hand corner of the puzzle? Will some of the newer techniques make it redundant?

George
Ruud
Site Owner
Site Owner
Posts: 601
Joined: Fri Dec 30, 2005 10:21 pm

Post by Ruud »

I will implement several solving techniques in the next version of HaniCue.

The 6 at the bottom of the July 19 puzzle can be removed, with the puzzle still having a single solution.

You can check this in the following way:

1. copy the puzzle to notepad;
2. Change the 6 to 0
3. Copy the changed puzzle and paste it back in the program.
4. When the reduced puzzle is invalid, the program will protest.

With the techniques I've found so far, I cannot solve it, but hey, I'm also new at this game :lol:

For your information:

The puzzle supplement in the Daily Telegraph coming weekend will include a hanidoku, with a reference to the website for solving tips. I hope the webserver can handle the traffic...

Maybe this will help build a community of people who can discover new solving techniques for this variant.
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
nj3h
Gold Member
Gold Member
Posts: 111
Joined: Mon Jul 10, 2006 12:58 pm
Location: Virginia / USA

Post by nj3h »

Ruud,
I did just what you suggested back on the 19th to determine if there was a unique solution to that puzzle without the extra 6. However, your program does not find a logical solution to it. Perhaps when the newer techniques are implemented, one will be found. Maybe the puzzle of the 19th will be a good test case for your upcoming program. However, if your new program doesn't solve it, it just means that there just might not be a logical way to do so or the technique hasn't been identified yet.

Congrats on having your HaniDoku puzzle published coming up this weekend. I wonder if it will be downloadable from their site.

I suspect people will be wanting HaniDoku Version 2 by next Sunday evening. LOL LOL.

One quick SudoCue question, is there a way to export just the string of 81 numbers, like the strings in the Clueless puzzles?

Regards,
George
Ruud
Site Owner
Site Owner
Posts: 601
Joined: Fri Dec 30, 2005 10:21 pm

Post by Ruud »

Congrats on having your HaniDoku puzzle published coming up this weekend.
Thanks. I'm very excited about this.
I suspect people will be wanting HaniDoku Version 2 by next Sunday evening.
I know some do already :lol: :lol:
is there a way to export just the string of 81 numbers, like the strings in the Clueless puzzles?
Go to the Options dialog, go to the Copy tab and click All Off and OK.
Now when you Copy with Ctrl+C (clues only) or Ctrl+F (all filled cells), you will have a single string of 81 numbers on the clipboard.

Ruud
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
Post Reply