# Weekly Challenge

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## Challenge #200: Sudoku Solver

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6 - Meteoroid

Finally got intermediate done! Going to see if logic works for the Advanced one if i modify my macro a bit.

Screenshots below could figure out how to upload workflow/macro if it doesn't count!

Workflow:

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Step 1: flip to grid

Step 2: Get all row and column values

Step 3: Input into Iterative macro

Step 4: Macro will loop until number is not found in either the column or row

This bottom part logic will have to change for the advanced one as it works if i loop 9x, seems to mess up if more than 9.

Step 5: Check against the intermediate solution:

L Mine R solution

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Alteryx Partner
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Check out the video solution containing all 3 solutions here: https://www.dataprepsolutions.com/2020/01/alteryx-weekly-challenge-200-lets-build.html

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8 - Asteroid

Intermediate level solution

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Alteryx Certified Partner

Solved, for any sudoku input!

Begginer + Intermediate

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Input and Solution

Macro

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8 - Asteroid

Following up with my advanced solution.

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15 - Aurora

Just started.

This is my first weekly challenge. Really exited 🙂

I was able to solve beginner and intermediate challenge.

Beginner

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Intermediate

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Really enjoyed it.

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12 - Quasar

Yay - 200!

Beginner

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Intermediate

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The advanced version will work as long as no trial and error is needed 🙂

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Alteryx

I finally was able to get back to this on the weekend and do the advanced part.

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I used an iterative macro similar to some of the other solutions. I'm going to try this on a number of advanced puzzles, I'm pretty sure that this relatively simple iterative elimination solution is going to run into problems on some of those since most of the code solutions I've seen use backtracking.

I have an additional output that shows the grid with any remaining candidates for unsolved cells to see where this algorithm falls over (if it does).

Edit: I just tested this with a sudoku rated as very hard and it failed to solve it. I added that sudoku to the workflow as a separate test input not connected to the workflow.
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Alteryx Certified Partner

Beginner and intermediate 🙂

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8 - Asteroid