68 lines
2.1 KiB
Python
68 lines
2.1 KiB
Python
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import itertools
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from solutions import BaseSolution
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class Solution(BaseSolution):
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input_file = '13.txt'
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layers = []
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scanners = []
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def __str__(self):
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return 'Day 13: Packet Scanners'
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def _move_scanners(self):
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for p, l in enumerate(self.layers):
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if l != 0:
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self.scanners[p][0] += self.scanners[p][1]
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if self.scanners[p][0] == l - 1 or self.scanners[p][0] == 0:
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self.scanners[p][1] = -self.scanners[p][1]
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def _init_scanners(self):
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self.scanners = [[0, 1] for l in self.layers]
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def _setup(self, puzzle_input):
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pi = [tuple(map(int, line.strip().split(': '))) for line in puzzle_input.splitlines()]
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self.layers = [0 for _ in range(pi[-1][0] + 1)]
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self._init_scanners()
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for k, v in pi:
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self.layers[k] = v
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def _get_severity(self):
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severity = 0
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for pos in range(len(self.layers)):
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if self.scanners[pos][0] == 0 and self.layers[pos] > 0:
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severity += self.layers[pos] * pos
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self._move_scanners()
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return severity
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def _will_be_caught(self):
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caught = False
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for pos, l in enumerate(self.layers):
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if l > 0 and self.scanners[pos][0] == 0:
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caught = True
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self._move_scanners()
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return caught
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def solve(self, puzzle_input):
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self._setup(puzzle_input)
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severity = self._get_severity()
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return severity
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def _scan(self, height, time):
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offset = time % ((height - 1) * 2)
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return 2 * (height - 1) - offset if offset > height - 1 else offset
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def solve_again(self, puzzle_input):
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# todo: rewrite!
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lines = [line.split(': ') for line in puzzle_input.splitlines()]
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heights = {int(pos): int(height) for pos, height in lines}
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wait = next(
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wait for wait in itertools.count() if not any(self._scan(heights[pos], wait + pos) == 0 for pos in heights))
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return wait
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if __name__ == '__main__':
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solution = Solution()
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solution.show_results()
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