Advent of Code 2023 Day 9 (BaseA Style)

Discussion thread for day 9 of the Advent of Code - https://adventofcode.com/2023/day/9

Accepted answers

All comments

Another breath of fresh air. Very satisfying problem to solve. Reminded me of my high school days, solving for the degree of a polynomial sequence (That knowledge didn't help a ton, but those were happy memories for a weirdo like me)!

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Main Workflow:
Main Workflow.png

Batch Macro (For part 1):
Part 1 Batch.png

"Reverse" Batch Macro (For part 2):
Part 2 Batch.png

Iterative Macro (Finds 'Predictions' for given input row):
Iterative Macro.png

Solution.yxzp

phottovy

Why does this feel like the calm before the storm...

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Macro:

aoc_ph_2023_09.yxzp

Gawa

Today's problem was not as difficult as yesterday.

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DaisukeTsuchiya

Today's one is easier than yesterday and can go out now!

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I reverse the input data for Part2 and it works well!
スクリーンショット 2023-12-09 150855.png

clmc9601

Pretty happy with my simple-looking no macro solution. Naturally, there's a long formula hidden inside. I like to generate formulas like that in Excel so there's fewer opportunities for typos and so that I can make changes efficiently.

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It's all thanks to @NicoleJ and GetPart() which means I can FINALLY iterate through a sequence of multiple numbers all stored in a single cell. Would not recommend for a real automation solution... but I have always wanted to do something like this for AoC. Too messy with left() and right() and regex_replace().

Screenshot 2023-12-09 001821.png

2023_AoC_clmc9601_Day_09.yxmd

kelsey_kincaid

Overall, I'm pretty happy with this one. Part 2 took me longer than it should have, because I made a small change right after reading the problem that threw off the rest of my logic. It took me awhile to remember I'd done that and to fix it. Regardless, I was able to use the same exact macro for both part 1 and part 2, which I count as a win in AOC.

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Part 1: I used an iterative macro to difference the data. Then I took that output and found the last row's value across iterations and summed them together with the last number in the sequence.

Part 2: Same approach, but I reversed the order of the data going into the macro. At some point I thought it was a good idea to reverse what value got subtracted from what value, which was a bad idea, and is what threw off my answer for part 2. I couldn't figure out why the identical logic I used for part 1 wasn't working, and it is because I was indeed NOT using identical logic. Regardless of how quickly (or slowly) I got there, it was refreshing for the answer to be as simple as reversing the sort order of the values.

Workflow:

Macro:

EDIT: Super intrigued by your approach @clmc9601 ! I can't dive into it right now because I'm on 2023.1 and missing one of the formulas you used, but I'm fascinated.

AOC2023_Day9_KelseyKincaid.yxzp

AkimasaKajitani

My solution. I've been recalling how to make the Iterative macro more and more.

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I heard that part 2 is reverse of the part 1 from @DaisukeTsuchiya , so I made the reverse input version for part 2.

Part 1 Macro

Part 2 Macro
I removed the result calculate part from part 1 macro.

Part 2 Reverse version macro(I only modified the final expressions. )

Day09.yxzp

Yoshiro_Fujimori

I don't have much chances to use Iterative macro in my daily business.

But this month I may use more cases than all I have used in the past

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Main

Batch for Part 1

Batch for Part 2

Iterative Macro to get the Next Value

AoC09.yxzp

AkimasaKajitani

I remake the workflow. I organize my workflow by working only what I should do.

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At part 2, I simply reverse the input from the part 1.

スクリーンショット 2023-12-09 220513.png

Day09_2.yxzp

ccanterman

Got it! I screwed up on my initial RegEx and dropped the negative signs. I ended up rebuilding the workflow 3 times and the macro twice (thanks @phottovy (again) for posting your workflow - it helped affirm I was doing the dang workflow right), getting the same wrong answer every time (which was frustrating at the time, but now makes me feel better) before finally catching the RegEx error. I'm going to sit and stare at a wall for awhile

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ccanterman

@clmc9601 - I wanted to do something like this but couldn't figure out how! I could see it in my brain but had no idea how to make it happen. It's so beautiful 😍

patrick_digan

Just a lot of copy/paste. Part 1 was intuitive but part 2 was not for me.

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Day9part2.yxmd

Qiu

I spent much time on part1 then realize the criteria I set for all the numbers become zero is incorrect.

I used Sum and there are cases like -1, -0 and 1, then the macro will stop to continue and gave me wrong result...

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SeanAdams

Fun and quick challenge today - gave time to catch up on day 5 :-)

There's a trick to this one too

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The trick here is that you don't need to keep all the data - the pyramid can be as wide as you like, it doesn't matter
You just need to keep (for every row other than the top row) the first and the last values - and that gives you part 1 and part 2

The iterative macro below goes across the first row - and you can go downwards to the bottom of the pyramid with a multi-row

Screenshot 2023-12-09 212957.png

2023_Day09-Part2.yxzp

DataNath

Day 9 completed! Definitely not as succinct as it could've been but just enjoying getting to the answers - another fun challenge and both parts run together in 1.6s.

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Day 9.yxzp

SuguruYoshinaga

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macro

day9.yxzp

leonhekkert

Took me longer than I like to admit.

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Day9.yxzp

AncientPandaman

seem like i built the shortest macro. but lot of dynamic rename involved.

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part1: forget the "-" was in the number
part2: try to use sum method as part1 not working. changed as instruction show.

workflow
Screenshot 2023-12-12 095218.png

macro

Day 09.yxzp

alisonpitt

AoC is finally helping me feel like I know what I'm doing with iterative macros 😊

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Day 9 - AP.yxzp

Gem

Never have I ever made 3 iterative macros for a single challenge... until AoC Day 9 😭🤣

However, now that this one's behind me, this one was pretty satisfying!

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Day 9.yxzp

caitlynmcintyre

I really enjoyed this one and Part 2 just involved changing the sort order of my data

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9.yxmd

9.yxmc

lwolfie

Always good to practice the iteration macros. I finally learned from everyone else to setup the example first.

Advent2023Day9.yxmd

leozhang2work

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Part 1

Part 2

Main Workflow

day 9.yxzp

DaisukeTsuchiya

I post again with solution in yxzp.

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Day9.yxzp

Samantha_Jayne

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Finally back on the wagon!

Loved the way that I could just reverse the values to make this work for my Star 2.
Not the most efficient, but the job got done and me back in the game.
I do need to refine my macro!!

AoC_2023_SamiJayne_Day9.yxzp

Laurap1228

Day 9 was fun

Advent of Code 2023.yxzp

Tokimatsu

Easy to understand.

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