Day 10 - cleanup

day10.py

@@ -4,84 +4,7 @@ from tools.coordinate import Coordinate
 from tools.grid import Grid
 from typing import Any
 
-VALID_NEIGHBOURS = {
-    Coordinate(1, 0): {
-        "check": ["F", "-", "L", "S"],
-        "valid": ["7", "-", "J"],
-    },
-    Coordinate(0, 1): {
-        "check": ["7", "|", "F", "S"],
-        "valid": ["J", "|", "L"],
-    },
-    Coordinate(-1, 0): {
-        "check": ["J", "-", "7", "S"],
-        "valid": ["F", "-", "L"],
-    },
-    Coordinate(0, -1): {
-        "check": ["L", "|", "J", "S"],
-        "valid": ["F", "|", "7"],
-    },
-}
 
-
-def remove_clutter(grid: Grid, start: Coordinate):
-    pipe_coords = set()
-    pipe_coords.add(start)
-    q = deque()
-    q.append(start)
-    while q:
-        cur = q.pop()
-        for c, v in VALID_NEIGHBOURS.items():
-            dc = cur + c
-            if dc not in pipe_coords and grid.get(cur) in v["check"] and grid.get(dc) in v["valid"]:
-                pipe_coords.add(dc)
-                q.append(dc)
-
-    for c in grid.getActiveCells():
-        if c not in pipe_coords:
-            grid.set(c, False)
-
-
-def get_farthest(grid: Grid, start: Coordinate) -> int:
-    q = deque()
-    q.append((0, start))
-    visited = set()
-    max_dist = 0
-    while q:
-        dist, cur = q.popleft()
-        if cur in visited:
-            continue
-        visited.add(cur)
-        for c, v in VALID_NEIGHBOURS.items():
-            dc = cur + c
-            if dc not in visited and grid.get(cur) in v["check"] and grid.get(dc) in v["valid"]:
-                q.append((dist + 1, dc))
-                max_dist = max(max_dist, dist + 1)
-
-    return max_dist
-
-
-def get_area(grid: Grid, start: Coordinate) -> set[Coordinate]:
-    if grid.get(start):
-        return set()
-    area = set()
-    q = deque()
-    q.append(start)
-    while q:
-        c = q.popleft()
-        if c in area:
-            continue
-        area.add(c)
-        for n in c.getNeighbours(includeDiagonal=True):
-            if grid.get(n):
-                continue
-            if grid.isWithinBoundaries(n):
-                q.append(n)
-
-    return area
-
-
-def walk(grid: Grid) -> int:
 LOOKUP = {
     "|": {
         Coordinate(0, 1): {"o_dir": [Coordinate(-1, 0)], "i_dir": [Coordinate(1, 0)], "n_dir": Coordinate(0, 1)},
@@ -141,6 +64,43 @@ def walk(grid: Grid) -> int:
     },
 }
 
+
+def remove_clutter(grid: Grid, start: Coordinate):
+    pipe_coords = set()
+    for x in LOOKUP[grid.get(start)]:
+        dir_ = LOOKUP[grid.get(start)][x]["n_dir"]
+        break
+    while start not in pipe_coords:
+        pipe_coords.add(start)
+        start += dir_
+        dir_ = LOOKUP[grid.get(start)][dir_]["n_dir"]
+
+    for c in grid.getActiveCells():
+        if c not in pipe_coords:
+            grid.set(c, False)
+
+
+def get_area(grid: Grid, start: Coordinate) -> set[Coordinate]:
+    if grid.get(start):
+        return set()
+    area = set()
+    q = deque()
+    q.append(start)
+    while q:
+        c = q.popleft()
+        if c in area:
+            continue
+        area.add(c)
+        for n in c.getNeighbours(includeDiagonal=True):
+            if grid.get(n):
+                continue
+            if grid.isWithinBoundaries(n):
+                q.append(n)
+
+    return area
+
+
+def walk(grid: Grid, part2: bool = False) -> int:
     cur = None
     for x in grid.rangeX():
         for y in grid.rangeY():
@@ -152,14 +112,17 @@ def walk(grid: Grid) -> int:
 
     assert grid.get(cur) == "F"
 
+    pipe_len = 0
     direction = Coordinate(0, 1)
     outside = get_area(grid, cur + Coordinate(0, -1))
     inside = set()
     visited = set()
     while cur not in visited:
+        pipe_len += 1
         visited.add(cur)
         cur += direction
         c = grid.get(cur)
+        if part2:
             oc = LOOKUP[c][direction]["o_dir"]
             ic = LOOKUP[c][direction]["i_dir"]
 
@@ -177,7 +140,10 @@ def walk(grid: Grid) -> int:
 
         direction = LOOKUP[c][direction]["n_dir"]
 
+    if part2:
         return len(inside)
+    else:
+        return pipe_len // 2
 
 
 class Day(AOCDay):
@@ -196,7 +162,7 @@ class Day(AOCDay):
         ],
     ]
 
-    def parse_input(self) -> (Grid, Coordinate):
+    def parse_input(self) -> Grid:
         grid = Grid()
         start = None
         for y, line in enumerate(self.getInput()):
@@ -227,15 +193,13 @@ class Day(AOCDay):
             grid.set(start, "-")
 
         remove_clutter(grid, start)
-        return grid, start
+        return grid
 
     def part1(self) -> Any:
-        grid, start = self.parse_input()
-        return get_farthest(grid, start)
+        return walk(self.parse_input())
 
     def part2(self) -> Any:
-        grid, _ = self.parse_input()
-        return walk(grid)
+        return walk(self.parse_input(), True)
 
 
 if __name__ == "__main__":