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-rw-r--r--Day3.lean2
1 files changed, 1 insertions, 1 deletions
diff --git a/Day3.lean b/Day3.lean
index e15e205..fbc9e3e 100644
--- a/Day3.lean
+++ b/Day3.lean
@@ -106,7 +106,7 @@ def part2 (schematic : Schematic) : Nat :=
Lean.HashMap.ofList $ schematic.numbers.bind $ λ pn ↦ pn.positions.map (·, pn)
let gearSymbols := schematic.parts.filter (Part.symbol · == '*')
-- but the symbols aren't enough, they need to be adjacent to **exactly** 2 numbers
- let numbersNextGearSymbols := List.dedup <$> gearSymbols.map λgs ↦
+ let numbersNextGearSymbols := List.eraseReps <$> gearSymbols.map λgs ↦
gs.position.adjacents.filterMap numberCoordinates.find?
let gearSymbols := numbersNextGearSymbols.filter (List.length · == 2)
let gearRatios := gearSymbols.map $ List.foldl (· * PartNumber.value ·) 1