From: Ben Harris <bjh21@bjh21.me.uk>
Date: Sat, 1 Jun 2024 14:16:29 +0000 (+0100)
Subject: 22a works on example
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~bjharris/git?a=commitdiff_plain;h=b497c1f79fbe58f1f3f71e462ce5ab2bda21b3ac;p=aoc-2022.git

22a works on example
---

diff --git a/22/22a.bqn b/22/22a.bqn
index 32abbe8..d21b3ee 100644
--- a/22/22a.bqn
+++ b/22/22a.bqn
@@ -6,10 +6,22 @@ Prep←{ ⟨ PrepMap ¯2↓𝕩, PrepPath ¯1⊑𝕩 ⟩ }
 Mark←{map𝕊⟨pos,dir⟩:
   ({𝕊⟨0,1⟩:'>';𝕊⟨1,0⟩:'v';𝕊⟨0,¯1⟩:'<';𝕊⟨¯1,0⟩:'^'}dir)⌾(pos⊸⊑) map
 }
+
 Main←{𝕊⟨map,path⟩:
+  Move←{
+    'L' 𝕊 ⟨pos,dir⟩: ⟨pos,⟨¯1,1⟩×⌽dir⟩;
+    'R' 𝕊 ⟨pos,dir⟩: ⟨pos,⟨1,¯1⟩×⌽dir⟩;
+    n 𝕊 ⟨pos,dir⟩: ⟨dir Advance⍟n pos,dir⟩
+  }
+  Advance←{dir 𝕊 pos:
+    dest←(≢map)|pos+dir
+    dest↩{ (≢map)|𝕩+dir } •_while_ { ' '=𝕩⊑map } dest
+    ('.'=dest⊑map)⊑⟨pos,dest⟩
+  }
   pos←⟨0,⊑(⊏map)⊐'.'⟩
   dir←⟨0,1⟩
-  map Mark⟨pos,dir⟩
+  ⟨⟨r,c⟩,d⟩ ← ⟨pos,dir⟩ Move´ ⌽path
+  (1000×1+r) + (4×1+c) + (|1-˜+´⟨2,1⟩×d)
 }
 
 •Show Main Prep •file.Lines ⊑•args