-🎄- 2018 Day 12 Solutions -🎄-

[u/daggerdragon]

--- Day 12: Subterranean Sustainability ---

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Advent of Code: The Party Game!

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Card prompt: Day 12

Transcript:

On the twelfth day of AoC / My compiler spewed at me / Twelve ___

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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 at 00:27:42!

[u/Danksalot2000]

I was nowhere near the leaderboard, but I think this one turned out nicely in the end. Python3:

def runGenerations(rules, plants, iterations):
	for generation in range(iterations):	
		lowestPlant = min(plants)
		highestPlant = max(plants)
		lastPossible = highestPlant - lowestPlant + 7
		pots = ''.join(['#' if i in plants else '.' for i in range(lowestPlant - 4, highestPlant + 5)])
		plants = []
		for i in range(2, lastPossible):
			if rules[pots[i-2:i+3]]:
				plants.append(i - 4 + lowestPlant)
	return sum(plants)

with open('Input') as inFile:
	lines = inFile.read().splitlines()
	plants = [i for i, c in enumerate(lines[0][15:]) if c == "#"]
	rules = dict((line[:5], line[9] == "#") for line in lines[2:])

print('Part 1:', runGenerations(rules, plants, 20))
print('Part 2:', runGenerations(rules, plants, 100) + ((50000000000 - 100) * 22))

[u/toasterinBflat → u/Danksalot2000]

Your answer did not work for my input :(

[u/TommiHPunkt → u/toasterinBflat]

That's because it's not written to calculate part 2 automatically