Day 3 Notes

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| Part 1 |
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$ elixir day3part1.exs
Travelled (969, 323) and encountereed 270 trees

Thoughts:

Input repeats, so use Stream.cycle/2.
Need to keep track of the x-offset, pass it to Enum.at/2.


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| Part 2 |
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$ elixir day3part2.exs
2122848000

Thoughts:

Modify original answer to take x and y velocity.
Can just pass x velocity in as before.
Use Enum.take_every/2 to skip unneeded rows for y velocity.

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| Overall Thoughts |
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Pretty simple, because Stream.cycle/2 takes care of the tricky bit.
Thankfully I answered part 1 in a way that made part 2 just a small change to add Enum.take_every/2.
In part 1, was tracking the travelled distance in antipication for part 2, but turns out it wasn't needed,
so stopped tracking the y value in the accumulator for part 2.