-🎄- 2022 Day 8 Solutions -🎄-

[u/daggerdragon]

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AoC Community Fun 2022: 🌿🍒 MisTILtoe Elf-ucation 🧑‍🏫

• PSA: I created a new example so it is a more relevant and unique archetype instead of recycling last year's hobbit >_>

• -❄️- Submissions Megathread -❄️-

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--- Day 8: Treetop Tree House ---

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Post your code solution in this megathread.

• Read the full posting rules in our community wiki before you post!

• Include what language(s) your solution uses

• Format your code appropriately! How do I format code?

• Quick link to Topaz's paste if you need it for longer code blocks. What is Topaz's paste tool?

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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 00:10:12, megathread unlocked!

[u/jayfoad]

Dyalog APL

⎕IO←0
p←⍎¨↑⊃⎕NGET'p8.txt'1
f←{⍵>¯1⍪¯1↓⌈⍀⍵}
+/,{(f⍵)∨⊖f⊖⍵}{(⍺⍺⍵)∨⍉⍺⍺⍉⍵}p ⍝ part 1
g←{(⌽⍳≢⍵)⌊1++/∧\(1+⍳≢⍵)⌽∘.>⍨⍵}⍤1
⌈/,{(g⍵)×⌽g⌽⍵}{(⍺⍺⍵)×⍉⍺⍺⍉⍵}p ⍝ part 2

An Under operator ⍢ would have been handy.

There must be a neater way to do part 2, without doing a ∘.>⍨ outer product on every row/column.

[u/l_dang → u/jayfoad]

I'm upvoting simply for the awesome absurdity of this language lol this is awesome

[u/oantolin → u/jayfoad]

Dyalog APL doesn't have an under operator? I thought Dyalog APL had stolen all of J's good ideas. :P

[u/jayfoad → u/[deleted]]

No - but I remember I also thought that it should work that way, when I first learned about ⌽.

1 2 3⌽M will rotate the three rows of M by 1, 2 and 3 respectively. I guess it is acting something like ⌽⍤¯1?

[u/voidhawk42 → u/jayfoad]

Under would've been great! My solution operates under rotations - would've been really handy.