64 lines
1.5 KiB
Python
Executable file
64 lines
1.5 KiB
Python
Executable file
#! /usr/bin/env python3
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import pathlib
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import re
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import sys
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from dataclasses import dataclass
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@dataclass
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class PasswordSpec:
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first: int
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second: int
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letter: str
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password: str
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def parse(puzzle_input: str):
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"""Parse input"""
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regex = re.compile(r"^(\d+)-(\d+) (\w): (\w+)$")
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def toInt(x):
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return PasswordSpec(int(x[0]), int(x[1]), x[2], x[3])
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return [toInt(regex.match(i).groups()) for i in puzzle_input.splitlines()]
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def part1(data):
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"""Solve part 1"""
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def test(x):
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return x.first <= x.password.count(x.letter) <= x.second
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# these two lines are equivilant.
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# return sum(1 for p in data if test(p))
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return len([1 for p in data if test(p)])
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def test_password(passwordSpec: PasswordSpec):
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if passwordSpec.password[passwordSpec.first - 1] == passwordSpec.letter:
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return passwordSpec.password[passwordSpec.second - 1] != passwordSpec.letter
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else:
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return passwordSpec.password[passwordSpec.second - 1] == passwordSpec.letter
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def part2(data):
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"""Solve part 2"""
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return sum(1 for p in data if test_password(p))
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def solve(puzzle_input):
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"""Solve the puzzle for the given input"""
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data = parse(puzzle_input)
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solution1 = part1(data)
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solution2 = part2(data)
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return solution1, solution2
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if __name__ == "__main__":
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for path in sys.argv[1:]:
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print(f"{path}:")
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puzzle_input = pathlib.Path(path).read_text().strip()
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solutions = solve(puzzle_input)
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print("\n".join(str(solution) for solution in solutions))
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