67 lines
1.4 KiB
Python
67 lines
1.4 KiB
Python
with open('input.text', 'r') as file:
|
|
data: list[str] = file.readlines()
|
|
|
|
topo_map = [[int(c) if c != '.' else -1 for c in line.strip()] for line in data]
|
|
|
|
x_bound: int = len(topo_map[0]) - 1
|
|
y_bound: int = len(topo_map) - 1
|
|
|
|
class Coord:
|
|
x: int
|
|
y: int
|
|
|
|
def __init__(self, x: int, y: int):
|
|
self.x = x
|
|
self.y = y
|
|
|
|
def __str__(self) -> str:
|
|
return f'({self.x}, {self.y})'
|
|
|
|
def __eq__(self, o) -> bool:
|
|
return o.x == self.x and o.y == self.y
|
|
|
|
def in_bounds(c: Coord) -> bool:
|
|
if c.y > y_bound or c.y < 0:
|
|
return False
|
|
|
|
if c.x > x_bound or c.x < 0:
|
|
return False
|
|
|
|
return True
|
|
|
|
def score_trail(c: Coord, last: int | None = 0) -> list[Coord]:
|
|
|
|
if not in_bounds(c):
|
|
return None
|
|
|
|
v: int = topo_map[c.y][c.x]
|
|
if v == 9:
|
|
return [c]
|
|
|
|
if v - last != 1 and last != 0:
|
|
return None
|
|
|
|
up, down, left, right = Coord(c.x, c.y - 1), Coord(c.x, c.y + 1), Coord(c.x - 1, c.y), Coord(c.x + 1, c.y)
|
|
|
|
nines = []
|
|
|
|
for dir in [up, down, left, right]:
|
|
if in_bounds(dir):
|
|
if topo_map[dir.y][dir.x] - v == 1:
|
|
for nine in score_trail(dir, v):
|
|
if nine not in nines:
|
|
nines.append(nine)
|
|
|
|
return nines
|
|
|
|
total = 0
|
|
for y, line in enumerate(topo_map):
|
|
for x, n in enumerate(line):
|
|
if n == 0:
|
|
total += len(score_trail(Coord(x, y)))
|
|
|
|
print(total)
|
|
|
|
|
|
|