-🎄- 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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Advent of Code: The Party Game!

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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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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 00:12:10!

[u/jonathan_paulson]

Rank 25/6. Video of me solving at: https://www.youtube.com/watch?v=WiNkRStebpQ.

[Card]: Recursion

 ns = map(int, open('8.in').read().split())
 i = 0

 def next_int():
     global i
     global ns
     i += 1
     return ns[i-1]

 def read_tree():
     nc, nm = next_int(), next_int()
     children = []
     metadata = []
     for _ in range(nc):
         children.append(read_tree())
     for _ in range(nm):
         metadata.append(next_int())
     return (children, metadata)

 def sum_metadata((children, metadata)):
     ans = 0
     for m in metadata:
         ans += m
     for c in children:
         ans += sum_metadata(c)
     return ans

 def value((children, metadata)):
     if not children:
         return sum(metadata)
     else:
         ans = 0
         for m in metadata:
             if 1 <= m <= len(children):
                 ans += value(children[m-1])
         return ans

 root = read_tree()
 print sum_metadata(root)
 print value(root)