Day 2 Notes

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Part1:
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$ elixir day2part1.exs
414

Thoughts:

Use a regex to parse the input
Huh, can't iterate a string with Enum. Split into a list with String.graphemes/1

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Part2:
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$ elixir day2part2.exs
413

Thoughts:

Convert indices to be zero-based.
No xor operator without importing Bitwise? Just write it manually.
Initially misread the problem - thought first position must match, and second position must not match,
which caused some confusion.
Probably rebound to the same variable names a bit too much - should work on clearer variable names.

After reading the elixir forum thread, String.at would have been fine for Part 2.
https://elixirforum.com/t/advent-of-code-2020-day-2

Also feel pretty dumb that I didn't realise bool != bool is effectively xor