151 lines
4.1 KiB
Plaintext
151 lines
4.1 KiB
Plaintext
[1]Advent of Code
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--- Day 23: LAN Party ---
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As The Historians wander around a secure area at Easter Bunny HQ, you come
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across posters for a [16]LAN party scheduled for today! Maybe you can find
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it; you connect to a nearby [17]datalink port and download a map of the
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local network (your puzzle input).
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The network map provides a list of every connection between two computers.
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For example:
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kh-tc
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qp-kh
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de-cg
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ka-co
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yn-aq
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qp-ub
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cg-tb
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vc-aq
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tb-ka
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wh-tc
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yn-cg
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kh-ub
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ta-co
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de-co
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tc-td
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tb-wq
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wh-td
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ta-ka
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td-qp
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aq-cg
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wq-ub
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ub-vc
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de-ta
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wq-aq
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wq-vc
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wh-yn
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ka-de
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kh-ta
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co-tc
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wh-qp
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tb-vc
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td-yn
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Each line of text in the network map represents a single connection; the
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line kh-tc represents a connection between the computer named kh and the
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computer named tc. Connections aren't directional; tc-kh would mean
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exactly the same thing.
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LAN parties typically involve multiplayer games, so maybe you can locate
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it by finding groups of connected computers. Start by looking for sets of
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three computers where each computer in the set is connected to the other
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two computers.
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In this example, there are 12 such sets of three inter-connected
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computers:
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aq,cg,yn
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aq,vc,wq
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co,de,ka
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co,de,ta
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co,ka,ta
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de,ka,ta
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kh,qp,ub
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qp,td,wh
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tb,vc,wq
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tc,td,wh
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td,wh,yn
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ub,vc,wq
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If the Chief Historian is here, and he's at the LAN party, it would be
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best to know that right away. You're pretty sure his computer's name
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starts with t, so consider only sets of three computers where at least one
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computer's name starts with t. That narrows the list down to 7 sets of
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three inter-connected computers:
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co,de,ta
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co,ka,ta
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de,ka,ta
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qp,td,wh
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tb,vc,wq
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tc,td,wh
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td,wh,yn
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Find all the sets of three inter-connected computers. How many contain at
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least one computer with a name that starts with t?
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Your puzzle answer was 1485.
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--- Part Two ---
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There are still way too many results to go through them all. You'll have
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to find the LAN party another way and go there yourself.
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Since it doesn't seem like any employees are around, you figure they must
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all be at the LAN party. If that's true, the LAN party will be the largest
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set of computers that are all connected to each other. That is, for each
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computer at the LAN party, that computer will have a connection to every
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other computer at the LAN party.
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In the above example, the largest set of computers that are all connected
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to each other is made up of co, de, ka, and ta. Each computer in this set
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has a connection to every other computer in the set:
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ka-co
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ta-co
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de-co
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ta-ka
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de-ta
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ka-de
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The LAN party posters say that the password to get into the LAN party is
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the name of every computer at the LAN party, sorted alphabetically, then
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joined together with commas. (The people running the LAN party are clearly
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a bunch of nerds.) In this example, the password would be co,de,ka,ta.
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What is the password to get into the LAN party?
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Your puzzle answer was cc,dz,ea,hj,if,it,kf,qo,sk,ug,ut,uv,wh.
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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 [18]return to your Advent calendar and try
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another puzzle.
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If you still want to see it, you can [19]get your puzzle input.
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References
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Visible links
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1. https://adventofcode.com/
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2. https://adventofcode.com/2024/about
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3. https://adventofcode.com/2024/events
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4. https://cottonbureau.com/people/advent-of-code
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5. https://adventofcode.com/2024/settings
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6. https://adventofcode.com/2024/auth/logout
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7. Advent of Code Supporter
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https://adventofcode.com/2024/support
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8. https://adventofcode.com/2024
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9. https://adventofcode.com/2024
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10. https://adventofcode.com/2024/support
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11. https://adventofcode.com/2024/sponsors
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12. https://adventofcode.com/2024/leaderboard
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13. https://adventofcode.com/2024/stats
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14. https://adventofcode.com/2024/sponsors
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16. https://en.wikipedia.org/wiki/LAN_party
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17. https://adventofcode.com/2016/day/9
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18. https://adventofcode.com/2024
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19. https://adventofcode.com/2024/day/23/input
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