day05.py

from math import inf

sections = open("input/day05.txt").read().split("\n\n")
seeds = [int(n) for n in sections[0][sections[0].index(":")+2:].split(" ")]
maps = [
    sorted(
        [[int(n) for n in entry.split(" ")] for entry in section.split("\n")[1:]],
        key=lambda x: x[1])
    for section in sections[1:]]

min_location = inf
for element in seeds:
    for ranges in maps:
        for map_range in ranges:
            if map_range[1] <= element and element < map_range[1] + map_range[2]:
                    element = map_range[0] + element - map_range[1]
                    break
    min_location = min(min_location, element)
print(f"a = {min_location}")

min_location = inf
seed_ranges = [(seeds[i*2], seeds[i*2] + seeds[i*2+1]) for i in range(len(seeds) // 2)]
for seed_range in seed_ranges:
    src_list = [seed_range]
    for ranges in maps:
        next_list = []
        for start, stop in src_list:
            for map_range in ranges:
                if map_range[1] <= start and start < map_range[1] + map_range[2]:
                    end = min(map_range[1] + map_range[2], stop)
                    offset = map_range[0] - map_range[1]
                    next_list.append((start + offset, end + offset))
                    start = end
                    if start == stop:
                        break
            if start != stop:
                next_list.append((start, stop))
        src_list = next_list
    min_location = min(min_location, min(x[0] for x in src_list))
print(f"b = {min_location}")