From 68555896de3510c560587433acec3470e289c999 Mon Sep 17 00:00:00 2001
From: sterni <sternenseemann@systemli.org>
Date: Tue, 20 Dec 2022 19:51:21 +0100
Subject: feat(sterni/aoc/2022): day20 BQN solution

This solution feels very un-BQN-esque, but I could not get it to work by
doing arithmetic operations on an array of indices for any input but the
example one. It's still decently fact considering that we create so many
intermediate arrays at each step.

Change-Id: I883409b4d99d4954312df9b9a9ffc568c39f7726
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7602
Reviewed-by: sterni <sternenseemann@systemli.org>
Autosubmit: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
---
 users/sterni/exercises/aoc/2022/20/20.bqn | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100644 users/sterni/exercises/aoc/2022/20/20.bqn

(limited to 'users/sterni')

diff --git a/users/sterni/exercises/aoc/2022/20/20.bqn b/users/sterni/exercises/aoc/2022/20/20.bqn
new file mode 100644
index 0000000000..8d4c905e87
--- /dev/null
+++ b/users/sterni/exercises/aoc/2022/20/20.bqn
@@ -0,0 +1,13 @@
+⟨ReadDec⟩ ← •Import "../../lib.bqn"
+enc ← ReadDec¨ •FLines "input"
+
+CoordSum ← +´∘(1000‿2000‿3000⊸((⊢≠⊸|+⟜(⊑∘(/=⟜0)∘⊢))⊏⊢))
+Mix ← {
+  M ← {m 𝕊 i:
+    l ← ≠m
+    i {n ← (l-1)|(𝕩⊑m)+⊑/𝕩=𝕨 ⋄ (n⊸↑(∾⟜𝕩)⊸∾n⊸↓) 𝕩(≠/⊢)𝕨}˜´ ⌽↕l
+  }
+  CoordSum ((⊢M⍟𝕨↕∘≠)⊏⊢) 𝕩
+}
+•Out "day20.1: "∾•Fmt 1 Mix enc
+•Out "day20.2: "∾•Fmt 10 Mix 811589153×enc
-- 
cgit 1.4.1