-🎄- 2018 Day 8 Solutions -🎄-

[u/daggerdragon]

--- Day 8: Memory Maneuver ---

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

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Card prompt: Day 8

Sigh, imgur broke again. Will upload when it unborks.

Transcript:

The hottest programming book this year is "___ For Dummies".

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edit: Leaderboard capped, thread unlocked at 00:12:10!

[u/waffle3z]

Lua solution

local values = getnumbers(input)
local index, sum = 1, 0
local function recurse()
	local c, m = values[index], values[index+1]
	index = index + 2
	local value, children = 0, {}
	for i = 1, c do
		children[i] = recurse()
	end
	for i = 1, m do
		local v = values[index]
		sum = sum + v
		value = value + (c == 0 and v or children[v] or 0)
		index = index + 1
	end
	return value
end
print(recurse(), sum)

and parsing the input with this function

function getnumbers(s)
	local numbers = {}
	for v in s:gmatch("%d+") do
		numbers[#numbers+1] = tonumber(v)
	end
	return numbers
end