forked from thib8956/advent-of-code-2k20
51 lines
1.2 KiB
Python
51 lines
1.2 KiB
Python
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#!/usr/bin/env python3
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import itertools
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def part1(inp):
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preamble_size = 25
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with open(inp) as infile:
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cleanfile = (int(l.rstrip()) for l in infile)
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for nums in window(cleanfile, preamble_size + 1):
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candidate = nums[-1]
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if not test_number(candidate, nums[:-1]):
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return candidate
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return -1
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def window(seq, n):
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it = iter(seq)
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result = tuple(itertools.islice(it, n))
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if len(result) == n:
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yield result
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for elem in it:
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result = result[1:] + (elem,)
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yield result
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def test_number(num, previous):
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sums = set(sum(x) for x in itertools.combinations(previous, 2))
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return num in sums
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def part2(infile, target: int):
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lines = [int(l.rstrip()) for l in open(infile).readlines()]
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total = 0
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visited = []
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for index, _ in enumerate(lines):
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i = index
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while total < target:
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total += lines[i]
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visited.append(lines[i])
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i += 1
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if total == target:
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return max(visited) + min(visited)
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visited.clear()
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total = 0
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if __name__ == "__main__":
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invalid_number = part1("input.txt")
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print("part1 ", invalid_number)
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print("part2 ", part2("input.txt", invalid_number))
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