21a: pull out opcode decoding

diff --git a/21/21a.bqn b/21/21a.bqn
index 50226b4562e77589350c19178e42375873083723..51d76b086687ba4599b8382ff6ff9fa5bf1c3ace 100644 (file)
--- a/21/21a.bqn
+++ b/21/21a.bqn
@@ -6,10 +6,10 @@ Prep←{
 Main←{
   monkeys←⟨⟩•HashMap⟨⟩
   {(⊑𝕩) monkeys.Set (1↓𝕩) }¨𝕩
+  _decode←{⊑("+-*/"⊐𝕗)⊏⟨+,-,×,÷⟩}
   Eval←{ 𝕊⟨number⟩: number;
     𝕊⟨x, opcode, y⟩:
-      op←⊑("+-*/"⊐opcode)⊏⟨+,-,×,÷⟩
-      (Eval monkeys.Get x) Op (Eval monkeys.Get y)
+      (Eval monkeys.Get x) opcode _decode (Eval monkeys.Get y)
   }
   Eval monkeys.Get "root"
 }