topic Re: Challenge #200: Sudoku Solver in Weekly Challenges

Challenge #200: Sudoku Solver

AYXAcademy — Tue, 13 Sep 2022 14:12:28 GMT

A solution to last week's challenge can be found here.

Challenge 200 represents another milestone (and badge!) on the trek up Mt. Everest: the arrival at Camp 4. To celebrate officially entering the Death Zone, we're serving up a challenge created by puzzler extraordinaire @TerryT!

Sudoku is a popular puzzle that requires you to the cells in a 9×9 grid with digits so that each row, each column, and each of the nine 3×3 boxes (shown with heavier lines) contains all the digits from 1 to 9 exactly once. Each puzzle is encoded as an 81 character string.

This challenge has three solution levels:

BEGINNER:
Using the Beginner and Intermediate Start File, parse the puzzle by separating rows nine characters at a time. The columns and boxes then line up accordingly where a ‘0’ represents an empty cell.

INTERMEDIATE:
Solve the puzzle provided in the Beginner and Intermediate Start File.

ADVANCED:
Solve the Sudoku puzzle from the Wikipedia article (Wikipedia Puzzle Start File).

Welcome to the Death Zone (Source: GIPHY)

Re: Challenge #200: Sudoku Solver

jacob_kahn — Mon, 27 Jan 2020 18:28:11 GMT

Solved Beginner Level

Re: Challenge #200: Sudoku Solver

estherb47 — Tue, 28 Jan 2020 01:29:15 GMT

Quickly solving to get that 200th challenge done. Beginner is done. Will post intermediate/advanced when I have more time to think on it

EDIT: Here we go. I didn't want to use a macro this time around. All macroed out from Advent of Code (which I'm still plugging through!)

Beginner:

Intermediate:

🙂

Re: Challenge #200: Sudoku Solver

JORGE4900 — Mon, 27 Jan 2020 18:42:25 GMT

Using one of my favorite tools--(Regex). First break down the 81 character line into 9 character chucks; rename the columns; transpose it; break it into 9 fields; rename the fields; and that is it.

Re: Challenge #200: Sudoku Solver

cplewis90 — Mon, 27 Jan 2020 18:59:34 GMT

Beginner completed. Need some more time on intermediate and advanced.

Re: Challenge #200: Sudoku Solver

RolandSchubert — Tue, 28 Jan 2020 10:47:56 GMT

Decided to solve it step by step - so this is my solution for the beginner part.

For the intermediate, I used a macro - and advanced will require some additional work.

Re: Challenge #200: Sudoku Solver

JamesCameron — Mon, 27 Jan 2020 19:01:56 GMT

My Beginner solution - the others will follow

Re: Challenge #200: Sudoku Solver

JohnJPS — Mon, 27 Jan 2020 19:11:44 GMT

My favorite, the R Tool, and another favorite, "Google to Kaggle to cut/paste and minimal tweaks."

Solves the Advanced also, but as noted, credit goes to Kaggle.

No spoiler picture other than the R tool. Would be fun to see it running as iterative macros, though (or via optimization).

Re: Challenge #200: Sudoku Solver

ChristinaFPE — Mon, 27 Jan 2020 19:13:19 GMT

Here's the Beginner portion solved. I need a bit more time to figure out the Intermediate and Advanced.

Re: Challenge #200: Sudoku Solver

TonyA — Mon, 27 Jan 2020 21:08:59 GMT

Beginner and Intermediate done. The Advanced is going to take some serious work...

Because the puzzle could be solved by simple elimination, I was able to get away without iterating at all. If there were multiple candidates after the first elimination I would have gone to an iterative macro.
I haven't looked at the advanced puzzle yet, but if it is even relatively hard, it could be really nasty. Most of the solutions I've seen use backtracking which would be fun to try in Alteryx although I'm not sure how without using Python.

Re: Challenge #200: Sudoku Solver

patrick_digan — Mon, 27 Jan 2020 19:34:10 GMT

I went for an iterative macro to solve the advanced part.

Re: Challenge #200: Sudoku Solver

bkclaw113 — Tue, 28 Jan 2020 13:36:42 GMT

Been a while since I tried my hand at one of these. Will need to keep working on the advanced solution.

A little sloppy on the Hard solution, but gets the job done.

Re: Challenge #200: Sudoku Solver

Aaron_Harter — Mon, 27 Jan 2020 20:41:26 GMT

Canvas:

Iterative Macro:

Re: Challenge #200: Sudoku Solver

jacrae — Mon, 27 Jan 2020 20:42:05 GMT

Finished beginner and intermediate!

Re: Challenge #200: Sudoku Solver

merigoalie1 — Mon, 27 Jan 2020 20:49:18 GMT

Here is my beginner solution. I'm still new to RegEx and originally I didn't know/see that you can tokenize into rows so my answer was extremely inefficient. After some research i got to a much simpler solution!

Re: Challenge #200: Sudoku Solver

JosephSerpis — Mon, 27 Jan 2020 20:49:45 GMT

Challenge Completed for the beginner part

Re: Challenge #200: Sudoku Solver

Kenda — Mon, 27 Jan 2020 21:11:37 GMT

Just getting back to work after vacation so starting with the beginner one so that I can get caught up!

Re: Challenge #200: Sudoku Solver

ggruccio — Mon, 27 Jan 2020 21:34:12 GMT

Solved the Advanced One! Wikipedia. Feels like a big accomplishment to get the right answer the first try!

Step1 - Determined all possible missing values across where the numbers 1-9 were present to get all valid rows
Step2 - Got all possible combinations of rows 1-3, 4-6, and 7-9 where numbers 1-9 resided in the 'cubes'
Step3 - Of what remained got all possible combinations where the columns contained 1-9.

This involved using append fields tool...and bringing column values into rows for logical testing (1-9).

Re: Challenge #200: Sudoku Solver

OllieClarke — Mon, 27 Jan 2020 21:27:41 GMT

Beginner and Intermediate challenges done, I'll be back for advanced I'm sure... Happy 200th everyone 😄

Re: Challenge #200: Sudoku Solver

hbraunius — Mon, 27 Jan 2020 22:58:13 GMT

My beginner and intermediate solution here.