Day 6 Notes
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| Part 1 |
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$ elixir day6part1.exs
6585
Thoughts:
So far I've read the whole file into memory. I initially did that here to get the answer
quickly to preserve my leaderboard position 🌟, but then refactored to use File.stream!
to parse the file line-by-line.
This meant using Stream.chunk_by to sort into groups.
Join all the answers together, and use Enum.frequencies/1 to count all the answers (discarding
newlines).
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| Part 2 |
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$ elixir day6part2.exs
3276
Thoughts:
Not stripping the newlines came in handy here, because I could use them to count how
many people are in each group. Then I could just count the frequencies that were answered
by the whole group, and finally sum those results.
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| Overall Thoughts |
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I didn't get an accurate time for this one due to having lunch between parts 1 and 2 🍝.
Got the answer under an hour including lunch, but more like two hours including streaming
the file and tidying up.
Using Map.pop/2 to remove an element and return its value at the same time is probably the
most notable thing here?
I wonder if there's a more effective way to parse the stream dynamically and also strip off
the new lines?
** Update **
From other people's answers, taking the intersection of all the replies was the best way
to implement this. Makes sense.
I think I'm succumbing to pressure to complete quickly due to the leaderboard, and just
going with whatever works rather than reading the question properly and working out
what it's *really* asking.
Adam Millerchip
39c28b5897