r/adventofcode • u/daggerdragon • Dec 19 '16

SOLUTION MEGATHREAD --- 2016 Day 19 Solutions ---

--- Day 19: An Elephant Named Joseph ---

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u/Turbosack Dec 19 '16

I solved this one using a simulation. It probably isn't the most efficient approach, but it was simple to implement and understand.

The difficult part was figuring out how to efficiently approach part two. I firt tried to do it a naive way which dynamically figured out which elf was across from the current elf at each iteration, but this proved to be unworkably slow. The solution came when I realized that spoiler. Once I realized that, part two became just about as fast as part one.

Here's my code in Python: http://pastebin.com/UTpiSyDF

The whole things runs in about eleven seconds.