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34 lines
1.0 KiB
Python
34 lines
1.0 KiB
Python
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from collections import OrderedDict
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def part1(crabs):
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moves = OrderedDict()
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for pos in range(min(crabs), max(crabs) + 1):
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# calculate total fuel required to move to pos:
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for crab in crabs:
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fuel_cost = abs(pos - crab)
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moves[pos] = moves.get(pos, 0) + fuel_cost
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min_move = min(moves, key=moves.get)
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print(f"Part 1, min move {min_move}, cost {moves[min_move]}")
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def part2(crabs):
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moves = OrderedDict()
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for pos in range(min(crabs), max(crabs) + 1):
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# calculate total fuel required to move to pos:
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for crab in crabs:
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dx = abs(pos - crab)
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# S = (n+1)(u0 + un)/2
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fuel_cost = dx * (dx+1)//2
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moves[pos] = moves.get(pos, 0) + fuel_cost
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min_move = min(moves, key=moves.get)
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print(f"Part 1, min move {min_move}, cost {moves[min_move]}")
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if __name__ == "__main__":
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with open("input.txt") as infile:
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crabs = [int(x) for x in infile.readline().split(",")]
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part1(crabs)
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part2(crabs)
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