tiny simplification

2024/day10.exs

@@ -9,16 +9,14 @@ defmodule Day10 do
   def find_trails(point, _grid, 9), do: [point]
 
   def find_trails({x, y}, grid, height) do
-    find_neighbours(x, y, height, grid)
+    find_neighbours(x, y, height + 1, grid)
     |> Enum.flat_map(fn {point, _} -> find_trails(point, grid, height + 1) end)
   end
 
   def find_neighbours(x, y, height, grid) do
-    next_height = height + 1
-
     grid
     |> Map.take([{x - 1, y}, {x + 1, y}, {x, y - 1}, {x, y + 1}])
-    |> Enum.filter(&match?({_, ^next_height}, &1))
+    |> Enum.filter(&match?({_, ^height}, &1))
   end
 
   def part2({grid, zeros}) do