... by: Ron, Thornhill On Canada

I could not find todays's (jan 20) entitled Legoman in your table of shapes
Andrew Stuart writes (24-Jan-2007):
I've no idea why, but in my Jigsaw Solver it's called 'Cyndie'

... by: Charlie Katz, Florida/NH, USA

Load Sudoku: 874001203010000090006300100400800010000060000060004005003005400050000020908100567

When coloring first shows up, all squares with 2s and 5s, the solver
removes one number when it could remove both 2s and 5s from
the commonly situated square. Why did it only remove one ? Seems
like a bug to me.
I really like your solver. When I get a *** or a **** in my daily paper, the first thing I do is load it so that I can print out a larger version and then I let the solver go to see if it will solve and also if it involves X-wings, Y-wings or coloring, because I still have trouble understanding how to look for those.
One day, there was a totally weird algorithm, something like Bernie's Bingo. This left me speechless. "Because this one isn't 4 or 7, that one is 9". I thought, "Someone's on windowpane". But I didn't take the time to read your more detailed description of the algorithm. I guess you've added a lot since I printed out the doc last spring. Its mindblowing. Keep up the good work.

Also, if possible, please use coloring to help to determine what has changed. The originally given numbers would be one color. Then the numbers that are changing in this current move another color. Then when the next move is occurring, all non-original, past changed another color. Thanks for your consideration. I have no idea how hard this would be to code.
Andrew Stuart writes (24-Jan-2007):
Hi Charlie, in this case you are correct, there are two identical single chains, one on top of the other. They are independent - the 2 and the 5 chains, although it could be re-expressed as an XY-Chain. The solver looks at numbers from 1 to 9 in that order so it's found the 2 first. It then quits and goes back to the start igoring the obvious 5. What you are seeing is the hightlighting for the 2 only, just so happens the 5 is also on the set of cells.

I could so arrange it to look for shorter chains before longer ones in which case it would get to the shorter 5-chain before the next longer 2-chain.

... by: fdan, NE USA

I like your solver. I put puzzles it to check for a single solution and to get a printable version and larger puzzle. Are puzzles usually symetric with their exposed values?
Thanks for a great solver.
Andrew Stuart writes (24-Jan-2007):
Puzzles are usually symetric but only at the discretion of the compiler who believes they are more aestetically pleasing. There is no logical reason for them to be symetrical. Our ones some times have the odd clue subtracted to make them a fraction harder which can make them slightly asymetric.

... by: Richard Proctor, Utah

I read Walter Hudiburg's comments about the helper and he is right, it is possible to solve any puzzle quickly. But I use the helper to teach me what is happening and to see if I've made any mistakes. This is a great aid and in it's present form has taught me a lot. I would hate to see it changed if the change doesn't allow us to learn and see our mistakes.

Andrew Stuart writes (24-Jan-2007):
Hi Richard, you will be able to use the solver on all puzzles - but I will make the change soon where the Daily and weekly ones are barred during their competition time. Thats only fair. You will be able to dig them out of the archive straight after the deadline and check and learn.

... by: Fumigator, Utah

I just want to write a comment to gush about how awesome I think your solver is.

>>>>>>> G U S H <<<<<<<

... by: charlie katz, Florida, NH, USA

Noticed that when we start filling in the board all of the loaded numbers are red, but as the board is advanced by your program some of those oriiginal values are changing to blue. This is confusing if I try to keep checking which of the new values are accurate in my incomplete puzzle.

... by: William Radcliffe, Redmond, WA

This is just a feature request for the printed puzzles. I find that having the candidate numbers arranged in a 9x9 grid more appealing visually.

I realiize that this is just personal preference, but wonder there is a way to accomplish it - maybe using style sheets and sending the puzzle down as XML

I am one of those people who is very tech savy and even own a table PC, but I still like to solve my puzzles on paper for some reason.

... by: fdan, NE USA

Is there a good reference on how to create a sudoku puzzle? Also how are puzzles classified as' easy, medium or hard...?
Thanks
Fdan

... by: r. jay poland, omaha, ne, 68105, usa

My comment has to do with not being able to look at the larger puzzle grid for an extended period of time due to high ratio of background color (white) to numbers (brown or blue). I'm wondering if others have requested using a larger font size in the large grid to make it a little less trying on the eyes?
Outside that, keep up the good work, it's the best site I have found. I most enjoy that it lets you know what it is doing rather than simply crunching out a solved puzzle and leaving you in the dark as to how the solution was derived.

... by: Edward Cross, Merrimack NH 03054

Load Sudoku: find sudoku with mul.

Mr Stuart:
Thank you for your web page. Do you know where I could
find sudokus with multiple solutions ?
Andrew Stuart writes (4-Jan-2007):
That's an unusual demand. I could make them, a small modification to my program. Exactly how many solutions do you want per puzzle?

... by: Walter Hudiburg, United States of America

Andrew, you are a true genius. With that said, let me add that I am very sad about your helper. It was a real challenge to do the sudoku puzzles, then the jigsaws, then the killers, by brainpower alone. It meant something to be at the top of the 300 list. Now all one has to do is go to the Sudoku helper, or not the jigsaw helper, type in the numbers, take the steps and watch the solution appear. And it can be done in under 10 minutes. So what?? I have made my views known on the forums about using computers to solve the puzzles. I still think it is wrong.
Andrew Stuart writes (4-Jan-2007):
Hi Walter, I'm very aware of the problem and I will be adding a stopper to the page as soon as possible. That was meant to have happened soon after the release but with Michaels passing away a whole load ot stuff has gone to the back burner. It is an important priority however. There will be a notice when its done.