My solutions for each task.

Goals and Non-Goals are similar to last year:

• Solve the puzzles.
• Solve them as quickly as possible.
• (optional) Refactor if something bothers me too much.
• Yet still: Have fun with the puzzles!
• Enjoy the coding practice and built up the "muscle memory" for Rust.
• Learn more Rust on the way.
• Become more confident.
• Allow rough edges here and there.
• Have fun!

• Performance and efficiency.

  Usually try to optimize for less to no allocations if possible. (Maybe next year I'll try to do a #![no_std]/embedded setup.)

  Input data gets embedded to also avoid the filesystem. This can bloat the binaries though.

• Relatively idiomatic Rust

  Although not all common patterns will be used; enums are usually common, but AoC puzzles mostly lend themselves to simple string and number crunching. Sometimes shorter code might be more preferrable than the Rusty code.

• The most, best, optimal, idiomatic way of writing Rust.1
• Perfectionism.
• Competition.

1 ^{Well, a bit of idiomatic code is probably still good.}

Multi-bin crate: Each day becomes its own binary, the CLI only needs switches for which part to run and if example inputs should be used.

• multiple binaries, one for each day
• binary name must include day value
• prepare task: create files and fetch input (needs session cookie)
• each day: create bin file, compile, prepare run, code solution, puzzle run

Each day prints its solution in the following format:

[D01.1] solution: 69177
 solved in 33.63μs

Single day helper:

# fish
function day; day$argv; day$argv -s; end
# and call it
day 5

To get a list of all days and parts:

### fish ###
for d in (seq 1 5); day$d; day$d -s; end
# as a self deleting function with input last
function aoc; for d in (seq 1 $argv); day$d; day$d -s; end; functions -e aoc; end; aoc 5
# or if you want to reuse it
function aoc; for d in (seq 1 $argv); day$d; day$d -s; end; end
aoc 5 # call this in your current shell session
### bash ###
for d in $(seq 1 5); do day$d; day$d -s; done
# as a self deleting function with input last
aoc() { for d in $(seq 1 1ドル); do day$d; day$d -s; done; unset -f aoc; }; aoc 5
# or if you want to reuse it
aoc() { for d in $(seq 1 1ドル); do day$d; day$d -s; done }
aoc 5 # call this in your current shell session

To get a binary runtime comparison with hyperfine:

hyperfine -N -w 100 "day{day}" "day{day} -s" -P day 1 5