97 lines
4.1 KiB
Plaintext
97 lines
4.1 KiB
Plaintext
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Advent of Code
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br0xen 40*
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• [About]
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• [Stats]
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• [Leaderboard]
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• [Settings]
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• [Log out]
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--- Day 13: Knights of the Dinner Table ---
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In years past, the holiday feast with your family hasn't gone so well. Not everyone gets along!
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This year, you resolve, will be different. You're going to find the optimal seating arrangement
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and avoid all those awkward conversations.
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You start by writing up a list of everyone invited and the amount their happiness would
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increase or decrease if they were to find themselves sitting next to each other person. You
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have a circular table that will be just big enough to fit everyone comfortably, and so each
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person will have exactly two neighbors.
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For example, suppose you have only four attendees planned, and you calculate their potential
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happiness as follows:
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Alice would gain 54 happiness units by sitting next to Bob.
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Alice would lose 79 happiness units by sitting next to Carol.
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Alice would lose 2 happiness units by sitting next to David.
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Bob would gain 83 happiness units by sitting next to Alice.
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Bob would lose 7 happiness units by sitting next to Carol.
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Bob would lose 63 happiness units by sitting next to David.
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Carol would lose 62 happiness units by sitting next to Alice.
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Carol would gain 60 happiness units by sitting next to Bob.
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Carol would gain 55 happiness units by sitting next to David.
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David would gain 46 happiness units by sitting next to Alice.
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David would lose 7 happiness units by sitting next to Bob.
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David would gain 41 happiness units by sitting next to Carol.
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Then, if you seat Alice next to David, Alice would lose 2 happiness units (because David talks
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so much), but David would gain 46 happiness units (because Alice is such a good listener), for
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a total change of 44.
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If you continue around the table, you could then seat Bob next to Alice (Bob gains 83, Alice
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gains 54). Finally, seat Carol, who sits next to Bob (Carol gains 60, Bob loses 7) and David
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(Carol gains 55, David gains 41). The arrangement looks like this:
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+41 +46
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+55 David -2
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Carol Alice
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+60 Bob +54
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-7 +83
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After trying every other seating arrangement in this hypothetical scenario, you find that this
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one is the most optimal, with a total change in happiness of 330.
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What is the total change in happiness for the optimal seating arrangement of the actual guest
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list?
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Your puzzle answer was 733.
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--- Part Two ---
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In all the commotion, you realize that you forgot to seat yourself. At this point, you're
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pretty apathetic toward the whole thing, and your happiness wouldn't really go up or down
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regardless of who you sit next to. You assume everyone else would be just as ambivalent about
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sitting next to you, too.
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So, add yourself to the list, and give all happiness relationships that involve you a score of
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0.
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What is the total change in happiness for the optimal seating arrangement that actually
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includes yourself?
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Your puzzle answer was 725.
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Both parts of this puzzle are complete! They provide two gold stars: **
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At this point, you should return to your advent calendar and try another puzzle.
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If you still want to see it, you can get your puzzle input.
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You can also [Shareon Twitter Google+ Reddit] this puzzle.
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References
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Visible links
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. http://adventofcode.com/
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. http://adventofcode.com/about
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. http://adventofcode.com/stats
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. http://adventofcode.com/leaderboard
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. http://adventofcode.com/settings
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. http://adventofcode.com/auth/logout
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. http://adventofcode.com/
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. http://adventofcode.com/day/13/input
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. https://twitter.com/intent/tweet?text=I%27ve+completed+%22Knights+of+the+Dinner+Table%22+%2D+Day+13+%2D+Advent+of+Code&url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F13&related=ericwastl&hashtags=AdventOfCode
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. https://plus.google.com/share?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F13
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. http://www.reddit.com/submit?url=http%3A%2F%2Fadventofcode%2Ecom%2Fday%2F13&title=I%27ve+completed+%22Knights+of+the+Dinner+Table%22+%2D+Day+13+%2D+Advent+of+Code
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