diff options
| -rw-r--r-- | 3.py | 19 |
1 files changed, 7 insertions, 12 deletions
@@ -1,34 +1,29 @@ -from typing import Generator from collections.abc import Iterable Bits = tuple[bool, ...] Input = list[Bits] -def column(rows: Iterable[Bits], n: int) -> Generator[bool, None, None]: - for row in rows: - yield row[n] - -def most_common(bits: Iterable[bool]) -> bool: - count1: int = 0 +def most_common(nums: Iterable[Bits], n: int) -> bool: + count: int = 0 length: int = 0 - for b in bits: - if b: count1 += 1 + for num in nums: + if num[n]: count += 1 length += 1 - return count1 >= length - count1 + return count >= length - count def bits_to_int(bits: Bits) -> int: return sum(b * 2 ** i for i, b in enumerate(reversed(bits))) def part1(nums: Input) -> int: nbits: int = len(nums[0]) - gamma: Bits = tuple(most_common(column(inp, i)) for i in range(nbits)) + gamma: Bits = tuple(most_common(inp, i) for i in range(nbits)) epsilon: Bits = tuple(not bit for bit in gamma) return bits_to_int(gamma) * bits_to_int(epsilon) def part2_impl(nums: Input, complement: bool, bit: int = 0) -> Bits: if len(nums) == 1: return nums[0] - target: bool = most_common(column(nums, bit)) ^ complement + target: bool = most_common(nums, bit) ^ complement nums = list(filter(lambda n: n[bit] == target, nums)) return part2_impl(nums, complement, bit + 1) |