advent-2022-python/advent/days/day04/solution.py
2022-12-04 06:24:52 +01:00

55 lines
1.6 KiB
Python

from __future__ import annotations
from dataclasses import dataclass
from typing import Iterator
day_num = 4
def part1(lines: Iterator[str]) -> int:
return sum(1 for line in lines if Pair.parse(line).includes())
def part2(lines: Iterator[str]) -> int:
return sum(1 for line in lines if Pair.parse(line).overlap())
@dataclass(slots=True, frozen=True)
class Range:
start: int
end: int
@staticmethod
def parse(line: str) -> Range:
match line.split('-'):
case [s, e]: return Range(int(s), int(e))
case _: raise Exception(f"Not a valid range: {line}")
def includes(self, other: Range) -> bool:
""" Check if this range includes the other """
return self.start <= other.start and self.end >= other.end
def overlap(self, other: Range) -> bool:
""" Check if this range obverlaps with the other """
return (self.start >= other.start and self.start <= other.end) or (
other.start >= self.start and other.start <= self.end)
@dataclass(slots=True, frozen=True)
class Pair:
first: Range
second: Range
@staticmethod
def parse(line: str) -> Pair:
match line.split(','):
case [f, s]: return Pair(Range.parse(f), Range.parse(s))
case _: raise Exception(f"Not a valid Pair: {line}")
def includes(self) -> bool:
""" Check if one range includes the other """
return self.first.includes(self.second) or self.second.includes(self.first)
def overlap(self) -> bool:
""" Check if the two ranges obverlap """
return self.first.overlap(self.second)