|
| 1 | +import functools |
| 2 | +from pprint import pformat |
| 3 | +from typing import Literal |
| 4 | + |
| 5 | + |
| 6 | +def cast_input(inputs: str): |
| 7 | + def parse_ls(line: str): |
| 8 | + info, name = line.split() |
| 9 | + return info if info == 'dir' else int(info), name |
| 10 | + |
| 11 | + def parse_output(output: str): |
| 12 | + if not output: |
| 13 | + return [] |
| 14 | + |
| 15 | + return list(map(parse_ls, filter(bool, output.split('\n')))) |
| 16 | + |
| 17 | + def parse_interactivity(interactivity: str): |
| 18 | + in_, out = interactivity.split('\n', maxsplit=1) |
| 19 | + return in_, parse_output(out) |
| 20 | + |
| 21 | + return list(map(parse_interactivity, filter(bool, inputs.split('$ ')))) |
| 22 | + |
| 23 | + |
| 24 | +class Pwd: |
| 25 | + def __init__(self): |
| 26 | + self._pwd: list[str] = [] |
| 27 | + |
| 28 | + def cd(self, d: str): |
| 29 | + if d != '..': |
| 30 | + return self._pwd.append(d) |
| 31 | + |
| 32 | + self._pwd.pop() |
| 33 | + |
| 34 | + @property |
| 35 | + def curr(self): |
| 36 | + return self._pwd[1:] |
| 37 | + |
| 38 | + |
| 39 | +class Dir: |
| 40 | + def __init__(self): |
| 41 | + self.dirs: dict[str, Dir] = {} |
| 42 | + self.files: dict[str, int] = {} |
| 43 | + |
| 44 | + def read_ls(self, pwd: list[str], infos: list[tuple[int | Literal['dir'], str]]): |
| 45 | + if pwd: |
| 46 | + p, *ps = pwd |
| 47 | + self.dirs[p].read_ls(ps, infos) |
| 48 | + return |
| 49 | + |
| 50 | + for info, name in infos: |
| 51 | + if info == 'dir': |
| 52 | + self.dirs[name] = Dir() |
| 53 | + continue |
| 54 | + self.files[name] = info |
| 55 | + |
| 56 | + @property |
| 57 | + @functools.cache |
| 58 | + def size(self): |
| 59 | + s = sum(self.files.values()) |
| 60 | + return s + sum(d.size for d in self.dirs.values()) # type: ignore |
| 61 | + |
| 62 | + def size_at_most(self, n: int): |
| 63 | + s = self.size if self.size <= n else 0 |
| 64 | + return s + sum(d.size_at_most(n) for d in self.dirs.values()) |
| 65 | + |
| 66 | + def __repr__(self): |
| 67 | + return pformat(self.files | self.dirs) |
| 68 | + |
| 69 | + |
| 70 | +def create_root(inputs: list[tuple[str, list[tuple[int | Literal['dir'], str]]]]): |
| 71 | + root = Dir() |
| 72 | + pwd = Pwd() |
| 73 | + for in_, out in inputs: |
| 74 | + if in_.startswith('cd '): |
| 75 | + cd, d = in_.split(maxsplit=1) |
| 76 | + pwd.cd(d) |
| 77 | + continue |
| 78 | + root.read_ls(pwd.curr, out) |
| 79 | + return root |
| 80 | + |
| 81 | + |
| 82 | +def part1(inputs): |
| 83 | + return create_root(inputs).size_at_most(100000) |
| 84 | + |
| 85 | + |
| 86 | +def part2(inputs): |
| 87 | + root = create_root(inputs) |
| 88 | + result = root.size |
| 89 | + target_size = 30000000 - (70000000 - root.size) |
| 90 | + q = root.dirs.values() |
| 91 | + while q: # bfs |
| 92 | + n = [] |
| 93 | + for d in q: |
| 94 | + size = d.size |
| 95 | + if size >= target_size: |
| 96 | + result = min(result, size) |
| 97 | + n.extend(d.dirs.values()) |
| 98 | + q = n |
| 99 | + return result |
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