2020-12-03 05:37:29 +00:00
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Day 3 Notes
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| Part 1 |
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+--------|
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$ elixir day3part1.exs
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Travelled (969, 323) and encountereed 270 trees
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Thoughts:
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Input repeats, so use Stream.cycle/2.
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Need to keep track of the x-offset, pass it to Enum.at/2.
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+--------+
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| Part 2 |
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$ elixir day3part2.exs
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2122848000
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Thoughts:
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Modify original answer to take x and y velocity.
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Can just pass x velocity in as before.
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Use Enum.take_every/2 to skip unneeded rows for y velocity.
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+------------------+
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| Overall Thoughts |
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Pretty simple, because Stream.cycle/2 takes care of the tricky bit.
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Thankfully I answered part 1 in a way that made part 2 just a small change to add Enum.take_every/2.
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2020-12-03 05:44:50 +00:00
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In part 1, was tracking the travelled distance in antipication for part 2, but turns out it wasn't needed,
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so stopped tracking the y value in the accumulator for part 2.
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