31 lines
746 B
Python
31 lines
746 B
Python
from __future__ import annotations
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from itertools import combinations
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from typing import Iterator
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day_num = 6
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def part1(lines: Iterator[str]) -> int:
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return marker(next(lines), 4)
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def part2(lines: Iterator[str]) -> int:
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return marker(next(lines), 14)
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def marker(line: str, length: int) -> int:
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"""
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Returns the position just after a marker. A marker has [length] non repeated characters.
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Raises Exception if no marker was found
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"""
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for pos in range(length, len(line)):
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found = False
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for a, b in combinations(line[pos - length:pos], 2):
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if a == b:
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found = True
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break
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if not found:
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return pos
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raise Exception("No marker found")
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