36 lines
1.3 KiB
Python
36 lines
1.3 KiB
Python
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# Returns the rise/run
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def slope(a: (int, int), b: (int, int)) -> (int, int):
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return (b[0] - a[0], b[1] - a[1])
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def inside(pos: (int, int), max: (int, int)) -> bool:
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return 0 <= pos[0] < max[0] and 0 <= pos[1] < max[1]
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if __name__ == '__main__':
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with open('input.data') as file:
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grid = [line.strip() for line in file]
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nodes = {}
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for y, row in enumerate(grid):
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for x, c in enumerate(row):
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if c == '.':
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continue
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if c in nodes:
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nodes[c].append((x,y))
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else:
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nodes[c] = [(x,y)]
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antinodes = set()
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for freq in nodes:
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print(f'Find all possible slopes given the starting positions of {freq}')
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for x,y in nodes[freq]:
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cur = (x,y)
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slopes = [slope(cur, (ox, oy)) for ox, oy in nodes[freq]]
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slopes = list(filter(lambda i: i != (0,0), slopes))
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antis = [(x + (i[0]*2), y+ (i[1]*2)) for i in slopes]
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antis = list(filter(lambda i: inside(i, (len(grid[0]), len(grid[1]))), antis))
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for a in antis:
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if a in nodes:
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print('found', a)
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antinodes.add(a)
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print(cur, '-->', slopes, 'antis ==>', antis)
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print('Total', len(antinodes))
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