diff --git a/aoc.bqn b/aoc.bqn
index b2769ab..9ec296e 100644
--- a/aoc.bqn
+++ b/aoc.bqn
@@ -112,30 +112,27 @@ aoc9 ⇐ {
 
 ################################################################################
 
-Fst ⇐ {0 ≡ ≠𝕩? @; ⊑𝕩}
-At  ⇐ {1⊑ ⊑ (⊑ ≡ 𝕩˙)¨⊸/ 𝕨} # use ⎊ for default
+At ⇐ {1⊑ ⊑ (⊑ ≡ 𝕩˙)¨⊸/ 𝕨} # use ⎊ for default
 
 aoc10 ⇐ {
-  BadScore1 ← ⟨')'‿3,']'‿57,'}'‿1197,'>'‿25137⟩⊸At⎊0
-  BadScore ← BadScore1 ∘ {'!'‿c: c; @}
+  BadScore1 ← ⟨')'‿3,']'‿57,'}'‿1197,'>'‿25137⟩⊸At
+  BadScore ← {'!'‿c: BadScore1 c; 0}
+
+  pairs ← Words "() [] {} <>"
 
   Step ← {
-    '!' ≡ Fst 𝕨? 𝕨;
-    𝕨 𝕊 ')': '(' = Fst 𝕨? 1↓𝕨;
-    𝕨 𝕊 ']': '[' = Fst 𝕨? 1↓𝕨;
-    𝕨 𝕊 '}': '{' = Fst 𝕨? 1↓𝕨;
-    𝕨 𝕊 '>': '<' = Fst 𝕨? 1↓𝕨;
-    ⊑ 𝕩∊"([{<"? 𝕩∾𝕨;
-    '!'‿𝕩
+    '!' ≡ ⊑⎊@ 𝕩?        𝕩;
+    𝕨 = pairs At⟜⊑⎊@ 𝕩? 1↓𝕩;
+    ⊑ 𝕨 ∊ ⊑¨pairs?      𝕨∾𝕩;
+    '!'‿𝕨
   }
-  Find ← ""⊸(Step˜´) ⌽
+  Find ← ""⊸(Step´) ⌽
 
   GoodScore1 ← ⟨'('‿1,'['‿2,'{'‿3,'<'‿4⟩⊸At
-  GoodScoreN ← {0 ((GoodScore1 ⊣) + (5⊸× ⊢))´ 𝕩}
-  GoodScore ← GoodScoreN ⌽ ∘ {'!' ≡ Fst 𝕩? ""; 𝕩}
+  GoodScore ← {'!' ≢ ⊑𝕩? 0 ((GoodScore1 ⊣) + (5⊸× ⊢))´ ⌽ 𝕩; 0}
 
   Middle ← ((⌊÷⟜2)∘≠ ⊑ ⊢) ∧ ∘ (0⊸≠¨⊸/)
 
-  A ⇐ +´ (BadScore∘Find¨) ∘ •FLines
-  B ⇐ Middle (GoodScore∘Find¨) ∘ •FLines
+  A ⇐ +´ BadScore∘Find¨ ∘ •FLines
+  B ⇐ Middle GoodScore∘Find¨ ∘ •FLines
 }