Advent of Code 2023 Day 12 (BaseA Style)

[AlteryxCommunityTeam]

Discussion thread for day 12 of the Advent of Code - https://adventofcode.com/2023/day/12

[gawa]

Finally finished D12P2. As 2 days has already passed, I upload my WF this time.

Spoiler

My WF looks very simple, but needed uncountable attempts to make this.... 

[DaisukeTsuchiya]

@Pang_Hee_Choy - Thank you so much for sharing super straightforward your solution.

I was stuck for so long time then I can get idea from your spoiler although I didn't download your WF. 
Finally I can finished after repeating debugging so many times. WF runs in 15 sec.
I can sleep tonight.

Spoiler

[AkimasaKajitani]

I struggled with Day12P2 but I finally got the second star!!!

I did not notice that the RegEx Match expression in a macro gave up to run, so it took me for long time.

 

Spoiler

Part 1 macro : simple macro

 

Part 2 macro:

 

In part 2 macro, I made it according to following term.

1. I convert rom ? to . and #
2. Create a definitive pattern on my own & delete the left-most number if it is already definitive.
3. Re-create Num.
4. Discard those that don't fit in the pattern check
5. Reduce the number of records by grouping and summing counts

This workflow takes 1 minutes to finish. 

[SeanAdams]

This is one of those days where it started out with brute force, and then Part 2 showed me the error of my ways.

It’s now running part 2 in ~17 sec – very happy with this solution!

Spoiler

Solution:

A few things that will help you as you think through this: 

• Alteryx works with spaces much easier than . characters
• A double . does the same job as a single – but it’s much easier to work with singles (because you can do a simple text match vs. target)
• Leading & trailing . characters don’t add value but they do add complexity

So here’s the recipe:

Parse the data

• change . to spaces;
• remove duplicate & leading / trailing spaces
• Build a target string of what you’re looking for – e.g. 1,1,3 will be #.#.###

Figure out valid combinations:

Repeat until you run out of strings with ? characters:

1. For each incoming row, Create 2 rows – one that replaces the first ? with a space; and one that replaces it with #
2. Trim leading & trailing spaces
3. Trim duplicate spaces
4. Throw away any strings which are shorter than the target
5. Figure out where the next ? is – call this X
6. Match the first X of my working string vs. the target – if it fails, discard
7. Then check if any of our working strings are the same – if so, then keep a counter
   1. E.g. instead of having 2 rows with ###??? – instead keep 1 row with a counter of 2
8. Loop

This works fast for a few reasons:

• Your number of rows that you are iterating with is very small because you compress them into a summary (step 7 above) and you are throwing stuff away as you go along
• You are using simple string matches each time (all the complexity of leading and duplicate spaces is gone)

[Tokimatsu]

Just one summarize tool in one place made it dramatically faster. I can't tell you how long it took me to do that.

Spoiler