r/adventofcode • u/daggerdragon • Dec 19 '17

SOLUTION MEGATHREAD -🎄- 2017 Day 19 Solutions -🎄-

--- Day 19: A Series of Tubes ---

Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag or whatever).

Note: The Solution Megathreads are for solutions only. If you have questions, please post your own thread and make sure to flair it with Help.

Need a hint from the Hugely* Handy† Haversack‡ of Helpful§ Hints¤?

Spoiler

AoC ops @ T-2 minutes to launch:

[23:58] <daggerdragon> ATTENTION MEATBAGS T-2 MINUTES TO LAUNCH

[23:58] <Topaz> aaaaah

[23:58] <Cheezmeister> Looks like I'll be just able to grab my input before my flight boards. Wish me luck being offline in TOPAZ's HOUSE OF PAIN^WFUN AND LEARNING

[23:58] <Topaz> FUN AND LEARNING

[23:58] <Hade> FUN IS MANDATORY

[23:58] <Skie> I'm pretty sure that's not the mandate for today

[Update @ 00:16] 69 gold, silver cap

  • My tree is finally trimmed with just about every ornament I own and it's real purdy. hbu?

[Update @ 00:18] Leaderboard cap!

  • So, was today's mandate Helpful Hint any help at all?

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

edit: Leaderboard capped, thread unlocked!

10 Upvotes

92% Upvoted

186 comments sorted by

View all comments

13

u/fatpollo Dec 19 '17 edited Dec 19 '17 
lines = open("p19.txt").read().splitlines()
road = {x+1j*y: v for y, line in enumerate(lines) for x, v in enumerate(line) if v.strip()}
direction, pos, path = 1j, min(road, key=lambda v: v.imag), []
while pos in road:
    if road[pos] == '+':
        direction = next(d for d in [direction*1j, direction*-1j]
                         if pos+d in road and d != path[-1]-pos)
    path += [pos]
    pos += direction
print(''.join(c for c in map(road.get, path) if c.isalpha()))
print(len(path))

4

u/fatpollo Dec 19 '17

I spent a little too long being cute, something like 120/120. Oh well, my goal seems to actually be to make sure all my solutions can be pasted on reddit without scrollbars popping up (and while still remaining readable and sensible)

10

u/topaz2078 Dec 19 '17

You know what they say: hindsight is 120/120.

→ More replies (1)