valbaca / advent-py

Advent of Code in Python

advent-py 🎄🐍

Advent of Code problems solved in Python

• Advent of Code

Running

# from the project root:
$ export PYTHONPATH=.
$ python advent/year2020/day1.py # or run open file from within VS Code
<part 1 answer>
<part 2 answer>

Just simple scripts: Each day's script runs solo (no top-level runner) and reads input from a .txt file with the same prefix in the same directory. For example day1.py reads day1.txt from within the same directory.

What's interesting?

• What's Advent of Code?
  • See Advent of Code's "About"
• Why Advent of Code?
  • It's fun! As opposed to grinding LeetCode, AoC has fun "flavor" and lets you solve however you want (any language or even none!). Lots of hidden easter eggs and nerdy references.
  • Non-prescriptive: you decide how you want to solve the problem: use whatever language, editor/IDE, debuggers, or libraries you want.
  • "Sneaky" concepts: I like how Advent questions are a bit subtle and uniquely challenging. What works for part 1 may not scale for part 2. Sometimes all it takes is some refactoring; other times a full rewrite might be necessary.
• elf.py - Santa's little helper! Where I put helper functions
  • For example, using __file__ within a python script gives the script filename. Then, changing the .py to .txt makes it simple to put the input file next to the script
  • septoi (stands for "separate, to int") is an incredibly useful helper. By safely "trying" to convert to int, it keeps the "non-number" parts as strings and gives ints where possible. It also accepts a regex to split on, so it's adaptive and flexible. This is a tangible advantage of dynamic typing.
• Why Python?
  • I've used AoC to get more familiar with other languages (Go, Clojure) and it's been a fun and useful approach.
  • I'm now looking to get more familiar with Python
  • Python is the #1 language for Advent of Code, and for good reason IMO. Most problems are solved in less than 100 lines of python
  • Compare to other languages, Python has significant advantages:
    • Python emphasizes the developer's time, which for these problems is a more crucial resource vs execution time
    • vs Java: Python is succinct, direct, and operates on a higher level (and just more fun!)
    • vs Go, Crystal, or Clojure: Python has a better debugger (or has one at all!)
    • vs Go or Java: Python's int (and dynamic typing in-general) is nicer than strict typing
    • Python is the slowest language to execute, but that's still fast enough. A "correct" solution typically comes down to using the right algorithm or data structures.

My Advent Progress

• Year 2015: 🎄 DONE! advent/year2015
  • Also solved in Go valbaca/advent-go and Clojure valbaca/advent
• Year 2016: 🎄 DONE!
  • Days 1-7, 12, 19, 22-25 in Python here: advent/year2016
  • Days 8-18 in Java: github.com/valbaca/advent
• Year 2017: ❄️ On ice.
• Year 2018: ❄️ On ice.
• Year 2019: ❄️ On ice.
• Year 2020: 🎄 DONE! advent/year2020
• Year 2021: 🎄 DONE! advent/year2021
• Year 2022: 🎄 DONE in Kotlin valbaca/advent-kt