42 lines
1.3 KiB
Python
42 lines
1.3 KiB
Python
from math import inf
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from tools.aoc import AOCDay
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from tools.int_seq import triangular
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from typing import Any, List
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def getMinFuelUse(crabs: List[int], increased: bool = False) -> int:
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min_num = min(crabs)
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max_num = max(crabs)
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avg = (min_num + max_num) // 2
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while 1:
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if increased:
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avg_fuel = sum(triangular(abs(avg - c)) for c in crabs)
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avg_fuel_p = sum(triangular(abs(avg + 1 - c)) for c in crabs)
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avg_fuel_m = sum(triangular(abs(avg - 1 - c)) for c in crabs)
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else:
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avg_fuel = sum(abs(avg - c) for c in crabs)
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avg_fuel_p = sum(abs(avg + 1 - c) for c in crabs)
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avg_fuel_m = sum(abs(avg - 1 - c) for c in crabs)
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if avg_fuel_m < avg_fuel:
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max_num = avg
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avg = (min_num + avg) // 2
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elif avg_fuel_p < avg_fuel:
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min_num = avg
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avg = (max_num + avg) // 2
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else:
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return avg_fuel
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class Day(AOCDay):
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test_solutions_p1 = [37]
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test_solutions_p2 = [168]
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def part1(self) -> Any:
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crabs = self.getInputAsArraySplit(",", int)
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return getMinFuelUse(crabs)
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def part2(self) -> Any:
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crabs = self.getInputAsArraySplit(",", int)
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return getMinFuelUse(crabs, True)
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