AoC2024_Day01.py

import re
import collections

infile = '../.input/day01.txt'
regex = r"(?P<La>\d*)(?:\s*)(?P<Lb>\d*)"

list_a = []
list_b = []

with open(infile) as f:
    for line in f.readlines():
        matches = re.match(regex, line)
        la, lb = matches.groups()
        list_a.append(int(la))
        list_b.append(int(lb))

a_sorted = sorted(list_a)
b_sorted = sorted(list_b)

diffs = sum([abs(b - a) for a, b in zip(a_sorted, b_sorted)])
print("Part 1: ", str(diffs))

count_b = dict(collections.Counter(list_b))
counts = [count_b.get(a,0)*a for a in list_a]
print("Part 2: ", str(sum(counts)))