44 lines
1,011 B
Text
44 lines
1,011 B
Text
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Day 15 Notes
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+--------+
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| Part 1 |
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+--------+
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$ elixir day15.exs 2020
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253
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Thoughts:
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Separate function to set the initial state.
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Store the last two round numbers for each answer.
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If it's the first time, store the same round number twice, which results in 0
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when subtracted.
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+--------+
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| Part 2 |
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+--------+
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$ elixir day15.exs 30000000
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13710
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Thoughts:
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I'm not sure if this was supposed to be brute-forcible.
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I think it is and that I designed the algorithm efficiently in the first part.
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The answer is a bit slow, but that's probably due to all the map updates. Using
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a more efficient data structure would probably speed it up - guessing this is
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faster in mutable languages.
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Anyway, no code changes here, so for this excercise I decided to combine the
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two answers, and just specify the last round via the command-line.
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+------------------+
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| Overall Thoughts |
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+------------------+
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Did this one pretty quickly. May even have time to go back to day 13 and learn
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about the Chinese Remainder Theorem...
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