advent-of-code/2023/d05/ex1/ex1.py

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2023-12-05 21:06:13 +01:00
#!/usr/bin/env python
import sys
from typing import NamedTuple
class AlmanacMapLine(NamedTuple):
dest_start: int
source_start: int
map_len: int
class AlmanacMap(NamedTuple):
lines: list[AlmanacMapLine]
def map(self, input: int) -> int:
for l in self.lines:
if input < l.source_start:
continue
if (l.source_start + l.map_len) <= input:
continue
return l.dest_start + (input - l.source_start)
return input
Almanac = dict[str, tuple[str, AlmanacMap]]
def solve(input: str) -> int:
def parse_almanac_map_line(line: str) -> AlmanacMapLine:
dest_start, source_start, map_len = map(int, line.split(" "))
return AlmanacMapLine(dest_start, source_start, map_len)
def parse_almanac_map(lines: list[str]) -> tuple[str, str, AlmanacMap]:
source, dest = lines[0].split(" ")[0].split("-")[::2]
map_lines = [parse_almanac_map_line(line) for line in lines[1:]]
return source, dest, AlmanacMap(map_lines)
def parse_almanac(paragraphs: list[str]) -> Almanac:
res: Almanac = {}
for raw_map in paragraphs:
source, dest, map = parse_almanac_map(raw_map.splitlines())
res[source] = dest, map
return res
def parse(input: str) -> tuple[set[int], Almanac]:
raw_seeds, *raw_almanac = input.split("\n\n")
seeds = set(int(n) for n in raw_seeds.removeprefix("seeds: ").split(" "))
return seeds, parse_almanac(raw_almanac)
def to_dest(almanac: Almanac, input: int, input_type: str, dest_type: str) -> int:
if input_type == dest_type:
return input
new_input_type, map = almanac[input_type]
return to_dest(almanac, map.map(input), new_input_type, dest_type)
seeds, almanac = parse(input)
return min(to_dest(almanac, seed, "seed", "location") for seed in seeds)
def main() -> None:
input = sys.stdin.read()
print(solve(input))
if __name__ == "__main__":
main()