Shidoku, Children Sudoku, Kids Sudoku

Shidoku, also known as Children Sudoku, is the smaller and easier 4x4 variant of Sudoku. Shidoku and Rokudoku(6x6 variant) are known as Kids Sudoku. All variants of Sudoku which has a smaller grid than the normal Sudoku are collectively known as Sub Doku.

Below is a sample puzzle of Shidoku. Fill in the grid so that every row, every column, and every 2x2 block contains the digits 1 through 4.

Related links
Mathematics of Shidoku:
1) Exploring the mathematics of Shidoku
2) Taking Sudoku Seriously

Sample Puzzles:
1) Free Kids Sudoku Puzzle
2) Kids Sudoku Puzzle
1) Sudoku for kids

Free printable online daily Sudoku puzzles for kids:
1) Sudoku.com.au (click on Kids Sudokus on the right panel)

Eh? First on Google search?

Some interesting facts turned up once I included the Google Analytics code on this blog. For those that don't know, Analytics is a tool that allows you to track visitors to your web site. It allows you to see page visits, visitor's region, bounce rate, etc.

One of the few things that I found is that a few hits to my blog actually come from search engines! This means that someone did a Google or Yahoo or a search on a search engine and found my blog. Out of curiosity, I googled "sudoku strategy squeezing" and voila, first on Google search!

Ironically, my new website is nowhere near top 10, and that's after some search engine optimization. Oh well, maybe I should chronicle my Sudoku programming journey as a separate blog and see if it attracts traffic.

SudSolver v0.21 is up

I have included the Jar executable now so there's no need to compile the code. Also, I have added a way for users to input their puzzle. Unfortunately, I couldn't get the clear button to work properly so if you wish to start a new puzzle, you need to close and open the program again.

Changelog
v0.21(march 19, 2009)
1) User can now input puzzle
2) Exit button

Interface and brute force search

I spent some time on my Sudoku program and now I have integrated graphical user interface to it. The menu bar still doesn't work though, so don't try to exit using file -> exit. Anyway, v0.2 is available now in the sidebar.

Brute force search has also been implemented. This means that any puzzle should be solvable now(provided of course, that the puzzle is valid). Of course, given the nature of brute force search, it may take a gadzillion years for the program to find the solution if the puzzle is too hard. So please be gentle on my program :p

I haven't been able to thoroughly test this program yet. So I can't say it's as bug-free as v0.1.