70 lines
1.7 KiB
Python
70 lines
1.7 KiB
Python
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import sys
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sys.path.append('../aoclib')
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from aoclib import Input
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def find_starting_points(field) -> list[tuple[int, int]]:
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points = []
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for y in range(len(field)):
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for x in range(len(field[0])):
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if field[y][x] == 0:
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points.append((x, y))
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return points
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def num_trails(point: tuple[int, int], curr: int, field: list[list[int]]) -> list[tuple[int, int]]:
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if out_of_bounds(point, field):
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return [None]
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x, y = point
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if field[y][x] != curr:
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# impossible path
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return [None]
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if curr == 9 and field[y][x] == curr:
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# goal
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return [point]
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curr += 1
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opts = list()
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opts.extend(num_trails((x+1, y), curr, field))
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opts.extend(num_trails((x-1, y), curr, field))
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opts.extend(num_trails((x, y+1), curr, field))
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opts.extend(num_trails((x, y-1), curr, field))
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return opts
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def out_of_bounds(point: tuple[int, int], field: list[list[int]]) -> bool:
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x, y = point
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return y < 0 or y >= len(field) or x < 0 or x >= len(field[0])
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def solve1(field: list[list[int]]) -> int:
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starts = find_starting_points(field)
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count = 0
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for p in starts:
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trails = num_trails(p, 0, field)
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count += sum([1 if n else 0 for n in set(trails)])
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return count
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def solve2(field: list[list[int]]) -> int:
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starts = find_starting_points(field)
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count = 0
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for p in starts:
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trails = num_trails(p, 0, field)
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count += sum([1 if n else 0 for n in trails])
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return count
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if __name__ == '__main__':
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#field = Input('input_test.txt').lines_split_as_ints()
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field = Input('input.txt').lines_split_as_ints()
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#part 1
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print('part 1:', solve1(field)) # 733
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#part 2
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print('part 2:', solve2(field)) # 1514
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