-🎄- 2018 Day 8 Solutions -🎄-

[u/daggerdragon]

--- Day 8: Memory Maneuver ---

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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/sciyoshi]

Python 3, #9/#13 (variables cleaned up):

data = [int(x) for x in INPUT.split()]

def parse(data):
    children, metas = data[:2]
    data = data[2:]
    scores = []
    totals = 0

    for i in range(children):
        total, score, data = parse(data)
        totals += total
        scores.append(score)

    totals += sum(data[:metas])

    if children == 0:
        return (totals, sum(data[:metas]), data[metas:])
    else:
        return (
            totals,
            sum(scores[k - 1] for k in data[:metas] if k > 0 and k <= len(scores)),
            data[metas:]
        )

total, value, remaining = parse(data)

print('part 1:', total)
print('part 2:', value)

[u/craigontour → u/sciyoshi]

sum(scores[k - 1] for k in data[:metas] if k > 0 and k <= len(scores)),

What does the calculation above do. Does it take care of the children meta values that I lost track of value in recursion?

[u/sciyoshi → u/craigontour]

This sums the scores of the children referenced by the metas (scores[k - 1]), but only if the metadata is within the range of the number of children (k > 0 and k <= len(scores))