## just another sudoku killer

Programs which generate, solve, and analyze Sudoku puzzles

### just another sudoku killer

Just another sudoku killer

Free program to solve sudokus: Sudokill-v11 ( http://homepages.ipact.nl/~allersma/all_lab.htm#soft )

Why should you use this program
- all known sudokus can be solved
- is not always fast, but why should it be fast
- only 75 kb
- DOS version; so it's simple in use (at least for me; I start with computers at 1970)
- common (news paper, books) sudokus are solved within 2 sec.
- unsusual ones need less than 3 minutes
- only twelve (up to now) extreme ones need more than 20 minutes (so you have a change to win from the computer)
- most common notations, used at forums, can be entered by drag and drop
- output file with several different notations is generated
- on request a version which elaborates batch files (one liners with noise) is available

How does the program work
Only three basic logical techniques are incorporated, being: single cell, naked single and naked pair.
Most common (newspaper) sudokus can be solved by these techniques. For experts this is boring stuff; so you can
stop the pragram after these steps, in order to continue by your self. The logical "solution" is also the
basis for further elaboration by the program. If you are choosing for continuing the program, a first trial
and error procedure is started. Randomly, two cells are choosen with two possibilities. The possibile
combinations are tested systematically, resulting in two extra clues. If no succes other pairs are selected.
A few seconds are required if the sudoku can be solved in this way. Only very difficult sudokus cannot be
solve by this procedure. A hihger level will be introduced, where the possibilities are tested cell
by cell (following a special sequence). Each time the previous mentioned procedures are elaborated.
This procedure can take several minutes. Only twelve sudokus (up to now) could not be solved by
these techniques. Therefore a killers level is introduced. A cell is choosen with the highest number of
possibilities (base on the three basic logicals). All possibilities are tested one by one, where all previous
methods are pass through. This procedure can take more than 30 minutes, but it solves all sudokus, known up to now.

I hope you will enjoy the program,

Marallas
merallas

Posts: 39
Joined: 26 September 2006

For those who are intersted in it I can inform you that a free program which can elaborate batches is added to my homepage. Only one-liners can be handled. However, a special feature is that you can put the source information in a file by drag and drop, which also can include non relevant information. The program will filter out the one-liners automatically. The solved sudokus are placed in separated files with different notations.
Sudokus with less than 17 clues are not elaborated. The program is not fast and some sudokus require a considerable amout of time. So if you want to solve thousends of sudokus then take some time.

Merallas
merallas

Posts: 39
Joined: 26 September 2006

As a final result of my programming activities in this field, a sudoku generator is available on my homepage. It took some time to get the program in a compact shape. The goal was to make a program which generates a file which can be printed as a booklet. The generated .txt file can be loaded into word. The result is better if bold chracters are used. A maximum of 999 sudokus can be generated in one batch.

Unfortunately I did not succeed up to now to generate the usual graphic notation in an automatically way. However, the actual notation is also clear and much space is available to make notations.
Nevertheless I am still looking for a program, which can transform a file with oneliners into a word document wit the standarized presentation.

The sudokus are not difficult to solve (newspaper level) , because only three logical techniques are involved. And is is not sure that the sudokus are unique.

merallas
merallas

Posts: 39
Joined: 26 September 2006