From: Ben Harris <bjh21@bjh21.me.uk>
Date: Thu, 6 Jun 2024 22:49:00 +0000 (+0100)
Subject: 23a: all proposals generated
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~bjharris/git?a=commitdiff_plain;h=905d12dbf25bbf71c2c9ba5ecb95224aa604217c;p=aoc-2022.git

23a: all proposals generated

But how to merge them?
---

diff --git a/23/23a.bqn b/23/23a.bqn
index 4c759dc..142ad49 100644
--- a/23/23a.bqn
+++ b/23/23a.bqn
@@ -1,5 +1,21 @@
 Prep←".#"⊸⊐∘>
 
-Main←⊢
+# Propose moving north if possible.
+ProposeN←{ ((1≠+´⥊𝕩)∧(0=+´⊏𝕩))/⟨[0‿1‿0,0‿0‿0,0‿0‿0]⟩ }
+
+Propose←{𝕊in: # Given a map of local area, say where Elf in centre will go.
+  ⊑ (∾{𝕏⁼¨ ProposeN 𝕏 in}¨{⌽∘⍉⍟𝕩}¨⟨0,2,3,1⟩) ∾ ⟨[0‿0‿0,0‿1‿0,0‿0‿0]⟩
+}
+
+# Same but propose empty array if there is no Elf.
+ProposeOr←{ (⟨1,1⟩⊑𝕩)∧Propose 𝕩 }
+
+Round←{𝕊map:
+  •Show map
+  ⟨h,w⟩←≢map ⋄ map↩»˘»(2+w)↑˘(2+h)↑map # Pad the map so windows work.
+  ⟨2,3,0,1⟩⍉ProposeOr⎉2⟨3,3⟩↕map
+}
+
+Main←Round⍟1
 
 •Show Main Prep •file.Lines ⊑•args