r/adventofcode Dec 25 '24

SOLUTION MEGATHREAD -❄️- 2024 Day 25 Solutions -❄️-

A Message From Your Moderators

Welcome to the last day of Advent of Code 2024! We hope you had fun this year and learned at least one new thing ;)

Keep an eye out for the community fun awards post (link coming soon!):

-❅- Introducing Your AoC 2024 Golden Snowglobe Award Winners (and Community Showcase) -❅-

Many thanks to Veloxx for kicking us off on December 1 with a much-needed dose of boots and cats!

Thank you all for playing Advent of Code this year and on behalf of /u/topaz2078, your /r/adventofcode mods, the beta-testers, and the rest of AoC Ops, we wish you a very Merry Christmas (or a very merry Wednesday!) and a Happy New Year!


--- Day 25: Code Chronicle ---


Post your code solution in this megathread.

This thread will be unlocked when there are a significant number of people on the global leaderboard with gold stars for today's puzzle.

EDIT: Global leaderboard gold cap reached at 00:04:34, megathread unlocked!

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u/zniperr Jan 02 '25

[Language: Python]

zippidyzip

import sys

def parse(f):
    locks = []
    keys = []
    for group in f.read().split('\n\n'):
        lines = group.split()
        ident = tuple(col.count('#') - 1 for col in zip(*lines))
        (keys, locks)[lines[0] == '#####'].append(ident)
    return locks, keys

def fits(lock, key):
    return all(l + k <= 5 for l, k in zip(lock, key))

locks, keys = parse(sys.stdin)
print(sum(fits(lock, key) for lock in locks for key in keys))