# Feedback and Questions

I've received a lot of interesting comments and questions from Sudoku fans over the last few years and this page
is where I try to answer them. Please feel free to drop me a note on the side of the page or try the Facebook
comment box. Or you can email me directly at andrew@str8ts.com.
**Post a Comment or Question here...**
## Sunday 13-Apr-2014

## ... by: Pat, Indiana

## Friday 28-Feb-2014

## ... by: Cathy, Edmonton, Alberta

Thank You,

Cathy

http://www.sudokuwiki.org/Daily_Jigsaw_Sudoku

?

The 30 day archive has puzzles on Monday which are the easiest.

Also, there is an easy jigsaw on

http://www.sudokuwiki.org/5_Daily_Puzzles_for_the_iPad

every day

## Friday 28-Feb-2014

## ... by: Nat Sothanaphan, Thailand

Load Sudoku: CLICK TO LOADI'm doing a project on Sudoku solver myself and I found your site a very great resource! However I think I found a bug in your program that you should know.

I got this Sudoku from http://norvig.com/sudoku.html. It has no solution. Your solver cannot solve it (or prove that there is no solution), but it deduces a naked pair 5,6 in H5, J5. However, when I plug in both possibilities, it can quickly determine that there is contradiction.

So I stared at the puzzle to see if there is a logical deduction without guessing. And I found it - row 8 actually has no cell with number 1 as a candidate! I think your solver should be able to detect this right away, but you probably missed it because the focus of the solver is not on the "no solution" puzzle. However this should be nice and easy to add :)

## Friday 28-Feb-2014

## ... by: Michael, UK

## Sunday 16-Feb-2014

## ... by: Dan, UK

the solver is perfect, also handling of solver. but I miss one (for me important) thing: a simple reset button for resetting puzzle to 'first given', mostly defined by url. because if I am doing tests of techniques, or want to start over in same puzzle, I have to refresh page. a simple 'reset puzzle' button, which wuld do a reset of puzzle would be very nice :)

thankx

Dan

So given that, a reset button is impossible to implement because there is nothing in the puzzle itself that says "this is the start". That is equivalent to asking "is this puzzle minimal" in the sense that all the clues are necessary. But some published puzzles are easier because they have extra clues and the minimal requirement is not a requirement for publishing.

But, we can brush all that aside by having the user decide the puzzle is at the start. So what you need is the "Save" and "Re-load" buttons which are above the small board. That does what you ask, but you need to remember to hit "save". I suppose if the puzzle information was in the URL a "restart" would be possible but I'd have to hide the button if the URL wasn't being used. I'll try that out.

## Saturday 15-Feb-2014

## ... by: Wayne, US

You don't normally go this far out...did you unintentionally omit a solved value?

My trial and error algorithm takes a full 30 seconds to solve (Escargot "only" takes 9 seconds).

## Friday 14-Feb-2014

## ... by: puzzler77, Texas, USA

Load Sudoku: CLICK TO LOADHere is a puzzle for anyone who loves Sudoku. I created it last summer.

puzzler77

## Tuesday 11-Feb-2014

## ... by: Tom, Eau Claire, WI, USA

Load Sudoku: CLICK TO LOADI do have a question though. Is there a FAQ? I graded the attached puzzle that I was having a bit of difficulty with and it graded it as "Tough". That makes me feel a little better knowing that it was a tough puzzle, but then I got to thinking what was the scale that this was on? How do I know that your not just placating me and making me feel good about myself. So I started looking for some help/information on your site regarding grading and the scale being used. I could not find anything. So I am wondering if you I missed it or if you might consider providing a page or a FAQ with the scale explained.

Thank you and keep up the great work!

Tom

http://www.sudokuwiki.org/Sudoku_Creation_and_Grading.pdf

What I need to do is provide a cut down page and link to it directly from the solver. Added to job queue

## Sunday 2-Feb-2014

## ... by: Dale E. Kloss, Portland, Oregon, USA

Am I missing something or is it possible to have an X Wing in a Sudoku X puzzle when one or both of the columns/rows in the rule is/are replaced by diagonal(s) ???

I am thinking of something like this:

picking 1 as the candidate value.

In column 2 have 1's in just A2 and D2.

On the diagonal have 1's in just A9 and D6.

The reasoning would be that we have locked 1's pairs in column 2 and locked 1's pairs in the diagonal on rows A & D thus the reasoning remains the same resulting in no other 1's in row A or row D .

Thanks- Dale Kloss

## Saturday 1-Feb-2014

## ... by: Julien RENARD, France

Best regards.

JR

Try the zero in the small board, I implemented it. Should work as discussed

## Monday 13-Jan-2014

## ... by: Amb, New Zealand

The advantage of using 0, is then you can type in your puzzle with one hand on a number pad!

Andrew