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