From: Ben Harris <bjh21@bjh21.me.uk>
Date: Tue, 14 May 2024 15:12:30 +0000 (+0100)
Subject: 14b kind of works but gives weird internal CBQN errors
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~bjharris/git?a=commitdiff_plain;h=c1e53f97c4017dbb3bab2f56c6fc1c6d4fa67983;p=aoc-2022.git

14b kind of works but gives weird internal CBQN errors
---

diff --git a/14/14b.bqn b/14/14b.bqn
new file mode 100644
index 0000000..c2ec017
--- /dev/null
+++ b/14/14b.bqn
@@ -0,0 +1,57 @@
+Split←{
+  blocknums ← +`𝕨
+  # Set entries in blocknums to -1 when they correspond with delimiters.
+  blocknums ↩ (¯1¨)⌾(𝕨⊸/) blocknums
+  blocknums⊔𝕩
+}
+
+_and_and_←{𝕨𝔽◶⟨0,𝕘⟩𝕩}
+_or_or_  ←{𝕨𝔽◶⟨𝕘,1⟩𝕩}
+
+Prep←{𝕊 lines:
+  {
+    fields←(⊑∘∊⟜" ->"¨𝕩) Split 𝕩 # Ewww
+    fields↩(0=4|↕≠fields)/fields
+    {
+      •ParseFloat¨(','=𝕩)Split𝕩
+    }¨fields
+  }¨lines
+}
+
+RectIndices←{
+  i←>𝕨⋈𝕩
+  (⌊˝i)⊸+¨⥊↕(1+⌈˝i)-(⌊˝i)
+}
+
+Plot←{
+  # Assume all co-ordinates are positive.
+  ⟨max_x, max_y⟩ ← (⟨1,3⟩+⌈˝>∾𝕩)
+  max_x ↩ max_x ⌈ 500+max_y
+  map←⟨max_x,max_y⟩⥊0
+  map ↩ 1¨⌾(¯1⊸⊏˘) map # Solid floor
+  {𝕊⟨from,to⟩:
+    map ↩ 1¨⌾((from RectIndices to)⊸⊑) map
+  }˘∾2↕¨𝕩
+  map
+}
+
+Main←{𝕊map:
+  grains←0
+  Settle←{
+    map 1⌾(𝕩⊸⊑) ↩
+    grains +↩ 1
+    1
+  }
+  # Return 0 if the sand falls forever; 1 once a path is full.
+  OnMap←{ (∧´𝕩≥⟨0,0⟩)∧(∧´𝕩<≢map) } # 0 if fallen off the map.
+  Solid←{ 𝕩⊑map } # Hit something solid.
+  FilledDown ←{Pour  ⟨0,1⟩+𝕩}
+  FilledLeft ←{Pour ⟨¯1,1⟩+𝕩}
+  FilledRight←{Pour  ⟨1,1⟩+𝕩}
+  Pour← OnMap _and_and_ (Solid _or_or_ (FilledDown _and_and_ FilledLeft _and_and_ FilledRight _and_and_ Settle))
+  Pour ⟨500,0⟩
+  #•Show (400↓map)⊏".#"
+  grains
+}
+
+•Show Main Plot Prep •file.Lines ⊑•args