Feedback and Questions

Great site Andrew. Just want to say thank you. I am learning so much about Soduku by taking your 'fiendish-sudoku' challenges as far as I can get and then using the solver to find the next step when I get stuck. Another happy fan ...

Just a quick note re: your web site. I think your web site is absolutely fantastic! I have used other sites to try to better understand how to solve Sudoku problems. None of the reference sites come close to yours. Not only has it helped me solve problems I coluldn't solve myself, I started understanding how to solve other ones much quicker on my own. Thank you for your effort in putting this site together for all of us who use it. And for free!!!

Andrew,

First off..Love your site! Best place online to try some truly difficult sudokus.

I was curious if you had given any consiedration to expanding the uniqueness strategy solvers to include extended gordonian rectangles, like the Franciscan Rectangle. For instance, in today's Daily Sudoju (05/18), after the initial simple solving methods, you get a board that looks like this:

+---------------+---------------+--------------+
| 5 2 149 | 6 3 149 | 7 148 48 |
| 6 17 147 | 147 8 2 | 35 35 9 |
| 89 1789 3 | 1479 147 5 | 6 14 2 |
+---------------+---------------+--------------+
| 3 6 58 | 1459 14 149 | 18 2 7 |
| 1 79 79 | 8 2 6 | 45 45 3 |
| 2 4 58 | 157 17 3 | 18 9 6 |
+---------------+---------------+--------------+
| 4 18 2 | 3 6 18 | 9 7 5 |
| 7 5 6 | 2 9 48 | 34 348 1 |
| 89 3 19 | 14 5 7 | 2 6 48 |
+---------------+---------------+--------------+


At B7,B8,E7,E8,H7,H8 you can see an extended gordonian rectangle. We know that H8 cannot be a 3 or 4 since that would give us multiple solutions, therefore H8 is an 8. After that, the puzzle solves itself.

The solver, however, does not pick that up. Just curious about adding that stratgey because the pattern, at least IMO, it seems to be one that is fairly easy to spot.

Again, thanks for the awesome site!

just wanted to let you know how much i appreciate your website. i enjoy the challenge of sudoku puzzles and you have helphed me get better at solving them. thank you for sharing and explaining your strategies. now if i could just understand a few more of them i would be a happy camper. never give up. thanks.

Enjoy your work very much! I have a new iPAD with latest updates and find it strange that the killer loads fine but the daily sudoku,puzzle only loads with funny red image blobs in each square where a puzzle predetermined answer should be. If I click on the iPad player it is not the same daily puzzle.

error in sudoku solver, version 1.84:
after NEW, the old simple colouring lines not cleard

Version 1,83
Procedure:
1. click "NEW"
2.input a puzzle on small board. Color of numbers on large board is blue.
3. click "SAVE". message => "board saved as cookie" click "OK"
4. click "Reload" => it use to change the color of the numbers to Red on the big board - now it DOESN"T -they remain blue. Also new numbers appear as if the "Take Step" had been clicked.

Hi Andrew,

I will buy it this week-end. One thing though ? It would seem to me that having a puzzle generator would be a great add-on to your solver. I like to do puzzles and then use your solver to see what I missed, how I could have done better, etc... Your puzzles are some of the best available. Why not offer that option . It would be a great combo.

When I try to clear board all the numbers remain in all the blocks,

This is the first Sudoku solver I've come across that is a serious help to the mentally challenged Sudoku fanatic! Well done!