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2024/Day04/README.md

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 ## --- Day 4: Ceres Search ---
-"Looks like the Chief's not here. Next!" One of The Historians pulls out a device and pushes the only button on it. After a brief flash, you recognize the interior of the [Ceres monitoring station](/2019/day/10)!
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+"Looks like the Chief's not here. Next!" One of The Historians pulls out a device and pushes the only button on it. After a brief flash, you recognize the interior of the __Ceres monitoring station__!
 As the search for the Chief continues, a small Elf who lives on the station tugs on your shirt; she'd like to know if you could help her with her <em>word search</em> (your puzzle input). She only has to find one word: <code>XMAS</code>.
 
-This word search allows words to be horizontal, vertical, diagonal, written backwards, or even overlapping other words. It's a little unusual, though, as you don't merely need to find one instance of <code>XMAS</code> - you need to find <em>all of them</em>. Here are a few ways <code>XMAS</code> might appear, where irrelevant characters have been replaced with <code>.</code>:
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 Read the [full puzzle](https://adventofcode.com/2024/day/4).
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+I used my proven tactic and converted the input to a Dictionary keyed by coordinates. It's easy to iterate over the keys and checking if we are in the bounds of the map as well.
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+Representing the coordinates with Complex numbers is also a useful way to deal with stepping in various directions.
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+The algorithm itself is simply a bruteforce check of all starting positions and reading orders.