Clean 2024 day 10.

src/holt59/aoc/2024/day10.py

@@ -1,3 +1,4 @@
+import itertools as it
 from typing import Any, Iterator
 
 from ..base import BaseSolver
@@ -7,40 +8,28 @@ def process(
     grid: list[list[int]], current: tuple[int, int]
 ) -> set[tuple[tuple[int, int], ...]]:
     row, col = current
+    value = grid[row][col] + 1
 
     if grid[row][col] == 9:
         return {((row, col),)}
 
-    result: set[tuple[tuple[int, int], ...]] = set()
-
-    for di, dj in ((-1, 0), (0, 1), (1, 0), (0, -1)):
-        i, j = row + di, col + dj
-
-        if i < 0 or i >= len(grid) or j < 0 or j >= len(grid[row]):
-            continue
-
-        if grid[i][j] != grid[row][col] + 1:
-            continue
-
-        for path in process(grid, (i, j)):
-            result.add(((row, col),) + path)
-
-    return result
+    return {
+        ((row, col),) + path
+        for i, j in ((row - 1, col), (row, col + 1), (row + 1, col), (row, col - 1))
+        if 0 <= i < len(grid) and 0 <= j < len(grid[i]) and grid[i][j] == value
+        for path in process(grid, (i, j))
+    }
 
 
 class Solver(BaseSolver):
     def solve(self, input: str) -> Iterator[Any]:
         grid = [[int(col) for col in row] for row in input.splitlines()]
-        n_rows, n_cols = len(grid), len(grid[0])
 
-        heads = [
-            (i, j) for i in range(n_rows) for j in range(n_cols) if grid[i][j] == 0
-        ]
+        paths = {
+            (i, j): process(grid, (i, j))
+            for i, j in it.product(range(len(grid)), range(len(grid[0])))
+            if grid[i][j] == 0
+        }
 
-        # for head in heads:
-        #     print(head, process(grid, head))
-
-        paths = {head: process(grid, head) for head in heads}
-
-        yield sum(len({path[-1] for path in paths[head]}) for head in heads)
-        yield sum(len(paths[head]) for head in heads)
+        yield sum(len({path[-1] for path in paths[head]}) for head in paths)
+        yield sum(len(paths_of) for paths_of in paths.values())