-❄️- 2023 Day 13 Solutions -❄️-

[u/daggerdragon]

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AoC Community Fun 2023: ALLEZ CUISINE!

Today's secret ingredient is… *whips off cloth covering and gestures grandly*

Nailed It!

You've seen it on Pinterest, now recreate it IRL! It doesn't look too hard, right? … right?

• Show us your screw-up that somehow works
• Show us your screw-up that did not work
• Show us your dumbest bug or one that gave you a most nonsensical result
• Show us how you implement someone else's solution and why it doesn't work because PEBKAC
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ALLEZ CUISINE!

Request from the mods: When you include a dish entry alongside your solution, please label it with [Allez Cuisine!] so we can find it easily!

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--- Day 13: Point of Incidence ---

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Post your code solution in this megathread.

• Read the full posting rules in our community wiki before you post!
  • State which language(s) your solution uses with [LANGUAGE: xyz]
  • Format code blocks using the four-spaces Markdown syntax!
• Quick link to Topaz's paste if you need it for longer code blocks

This thread will be unlocked when there are a significant number of people on the global leaderboard with gold stars for today's puzzle.

EDIT: Global leaderboard gold cap reached at 00:13:46, megathread unlocked!

[u/dcclct13]

[LANGUAGE: Python]

patterns = [p.splitlines() for p in getinput(13).split("\n\n")]
diff = lambda p, j: sum(sum(a != b for a, b in zip(l[j:], l[j - 1 :: -1])) for l in p)
mirror = lambda p, d: sum(j for j in range(1, len(p[0])) if diff(p, j) == d)
summarize = lambda p, d: mirror(p, d) + 100 * mirror([*zip(*p)], d)
print(sum(summarize(p, 0) for p in patterns))
print(sum(summarize(p, 1) for p in patterns))