Sudoku Solving Program Using 'C'

Hey I dont know how to play the game but never the less I just went through the codes and also ran the exec and I was impressed by the output of the board. Also its well documented and readable but its better if the code comments can be used to generate a documents that can be refered and so I Document your code thread might be useful to you if you havent gone through it before.

I don't quite understand Shabbir - is it that u don't know to play the GAME or play the 'C' program. With the assumption that it is the latter, I proceed.

I apologize for not incorporating a "How to Play" option within/outside the program or along with the documentation (which I know is pretty amateurish).

So, I will try to elaborate on how to use the program :

How to get the Puzzle Solved by the Computer (Choice 1 of Main Menu)

1. Just select a suitable newspaper (preferrably Mumbai Mirror or some paper that gives a
minimum of 26-30 entries - anythin less & u will SURELY NOT get a proper solution)

2. Count the no. of entries that is GIVEN/made available in the paper's puzzle
(I am sorry the counting too has to be done manually - didn't give it much thought in the
beginning - now i realize, that its probably a little cumbersome - will make changes to
that)
This number must be entered in the "Enter the number of nos to be entered : " prompt

3. Now, just enter the entries in the following format :
RowNo <Space> ColNo <space> Entry_to_be_placed

4. If u dislike the above format of I/P, go to the "Change Settings" choice & change the I/P
settings, after which the I/P format becomes :
For Row 1:
ColNo <space> Entry_to_be_placed
.
.
.
0 <space> 0



For Row 2:
ColNo <space> Entry_to_be_placed
.
.
.
0 <space> 0


& So on....

Please Note, that the '0's indicate the termination of I/P for the present row. Also, note
that both 0's should be fed.


5. Sit back & let the program do ur work(hopefully)
Check if the solution presented on screen matches the solution in the paper (hopefully,
it will)

6. Also, the O/P mode by default shows all the Recursive calls. For those of us, who want
to view the final solution without knowing how the hell its been done, u can go to the
"Change Settings" option & change the O/P settings



How to Store the Puzzle & Solution to the Puzzle using the Prog (Choice 2 of Main Menu)

Steps 1 thru 3 remain same as above

NOTE: I hav NOT incorporated the 2nd I/P mode in this section (my memory - it fails me
sometimes). So, I hope that u can fill in that gap.


4. Now, feed in the Solution of the puzzle as I/P Row-wise
i.e.
Row 1:
C1 E1
C2 E2
C3 E3
.
.
C9 E9

Row 2:
C1 E1
C2 E2
C3 E3
.
.
C9 E9

.
.
.
.
Row 9:
C1 E1
C2 E2
C3 E3
.
.
C9 E9




Also, once u hav changed the settings, it doesn't go back to default settings automatically.
U must set it back to default settings by going to "Change Settings" choice & choosing the "Restore All Defaults" option


Hope that is sufficient guidelines to at least start getting acquainted with the I/P-O/P of the
prog.


Ciao,
Rajiv


PS : A very eventful B-day to you.

I dont know how to play the sudoku.

Well, in that case, u can just refer any News-paper's Sudoku section. They give the rules along with the puzzle - that should be sufficient for u to understand or u can search in Google for the Rules.

To make your work easier, I will describe the rules here :


Board Layout :
1. 9 Row, 9 Column Board - i.e. board with 81 sub-blocks.

2. The Board can be divided into 9 sub-grids, each of which consists of 3 Rows, 3 Columns - i.e. 9 sub-blocks (For more idea on the sub-grids, refer the documentation - its given their pictorially)



Objective/Mission :
U must fill the Sudoku Board with numbers 1 to 9 using the following guidlines :
> Each Row must contain all the numbers from 1 to 9
> Each Column must contain all the numbers from 1 to 9
> Each Sub-grid must contain all the numbers from 1 to 9
> NO Repetition of numbers must take place along a Row/Column or in a Sub-Grid



What is Given to u :
---> Some of the Numbers varying from 1 to 9 are placed in different sub-blocks &
are already made availble initially - we must place the remaining numbers correctly

---> Depending upon the number of nos. already made available (AND ALSO THEIR
PLACEMENTS)- Sudoku's r classified as Easy, Medium, Hard & Evil

---> Easy Sudoku implies that at least 28-30 entries will be given to u, that too placed in
such a way, that the puzzle is easy to solve. My program can only ATTEMPT to solve
such puzzles.



Hope that is sufficient to at least get u introduced to the Game.

Anyways, the program doesn't need u to be an xpert in it. It isn't an interactive platform, where u can play the game - what it does, it SOLVES (or attempts to) a given (Easy Level) Sudoku Puzzle, when the numbers already given in the Puzzle r fed as I/P.


Ciao,
Rajiv

Also, visit the Site I hav mentioned in the "Credits" section to understand the Algorithm used.

And visit the sites to know more bout the game/rules & if u want to try ur hand at Sudoku :
1. http://www.lovatts.com.au/sudoku/sudoku.htm
2. http://jayisgames.com/archives/2005/06/web_sudoku.php


Ciao,
Rajiv

Hello guys, I am attaching a Zip File that contains :

1. "sud_use_as_base.c" - This is a 'C' file that u can use to build ur own Sudoku Programs - it does the work of I/P & O/P. So half of ur coding work is reduced.

2. "coded_ip_4_sdku.rtf" - This is a Wordpad file that contains some Sudoku's in the coded form (coded as per the I/P requirements of the program)

3. "save_sud_sols.txt" - This is a text/Notepad file that contains the Questions & Solutions to some Sudoku Puzzles, which u can try as Test I/Ps for the Sudoku Program. U can then match & see if the solution matches or not & can hav a better understanding of where the program fails.


Note : Use the 2nd & 3rd file simultaneoulsy - use the 2nd one for I/P & 3rd file for checking the O/P.


Hope that helps u guys to analyse the prog better!

Ciao,
Rajiv

I just googled it out and bookmarked the link but when I get a bit of time will see and play to it.

Hello guys,
Happy New Year 2006 to u all !!

Right, then, after settling that, I come to the point. I have found out why the code wasn't working.

I am attaching the rectified Program, along with updated documentation, to reflect the innumerable, small changes I hav made to the code.

Also, the main logical function : "solve_easy_level( )" is NOT a Recursive Function any more - I found that it could be implemented Non-recursively, thereby increasing time-space efficiency of the program.

Now, I think, you experts might find it worthwhile to go through the program & give me a feedback.

Ciao,
Rajiv

Do you have GUI for this program as well.Im interested to see how it looks like.
Befor I've tried doing this program.Using not so good GUI.