Creating a grid

SaphuA · Posted: Sat Oct 08, 2005 11:19 am Post subject: Creating a grid

Hi,
Right after my post, with the completed grid, I figured that my method for creating a sudoku grid (all numbers filled) was kinda crappy. Even though it was a legal grid, ther was this repeating lines in there which made it look unreal (hard to explain, just take from me it sucked Wink

)

fyi, I'm using Flash to code this Rolling Eyes

So I'm not rewriting the grid using a totaly different approach.
Here's what I'm doing in short terms:
- The first cell [0,0] is filled the 9 numbers, each at a random position.
- The second cell [0,1] will be filled while taking care of the numbers on the first cell
- The tirth cell will be filled with the numbers that are left when looking at the numbers on the rows from cell [0,0] and [0,1]. And will randomly be placed.
- This will also be repeated for vertical

So then I get the folowing (so far so good) grid:

Ruud · Site Admin

Hi SaphuA,

I did use the same method you use, and ran into similar problems. There are a few topics in the Setting Sudoku section that cover this subject, but they're a bit hard to find.

This is how I circumvented the problem:

1. Abandon the box-by-box approach. Just randomly place digits in the grid.
2. Keep track of the number of candidates left for each cell after placing a digit. No advance logic or anything, just cells blocking eachother out.
3. Sort the remaining cells by number of candidates. If there's any cell with no candidates left, you must either backtrack or restart.
4. To avoid bias (creating the same solution every time), assign a random number to each cell when you start this process. Then sort on available candidates and random number when 2 cell have the same number of candidates.

This must give you a good solution within 1-3 attemps (faster when you implement backtracking in stead of restart)

Good luck

SaphuA · Posted: Sun Oct 09, 2005 2:22 pm Post subject:

Just thought I might notify you guys, Ruud has been helping me over PM for the last two days, and I finaly did it Smile

I'm pretty happy about this, since I was using totaly wrong approaches for the last 2 weeks, which all ended up worthless. So after 4 engines I finaly did it Wink

Here are some results (please note that it was made in Flash, hence the speed Wink

):

mo_vengeance · Posted: Mon Dec 19, 2005 11:10 pm Post subject: generating grid

So would you mind sharing the code you used to generate these grids? I'm trying to make an image-based Sudoku-like game (vs. number-based) using movie clips, and I fear I'm in over my head! Grid-generator code would be most helpful!