Day 3: Mull It Over
Megathread guidelines
- Keep top level comments as only solutions, if you want to say something other than a solution put it in a new post. (replies to comments can be whatever)
- You can send code in code blocks by using three backticks, the code, and then three backticks or use something such as https://topaz.github.io/paste/ if you prefer sending it through a URL
FAQ
- What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
- Where do I participate?: https://adventofcode.com/
- Is there a leaderboard for the community?: We have a programming.dev leaderboard with the info on how to join in this post: https://programming.dev/post/6631465
I couldn’t figure it out in haskell, so I went with bash for the first part
Shell
cat example | grep -Eo "mul\([[:digit:]]{1,3},[[:digit:]]{1,3}\)" | cut -d "(" -f 2 | tr -d ")" | tr "," "*" | paste -sd+ | bc
but this wouldn’t rock anymore in the second part, so I had to resort to python for it
Python
import sys f = "\n".join(sys.stdin.readlines()) f = f.replace("don't()", "\ndon't()\n") f = f.replace("do()", "\ndo()\n") import re enabled = True muls = [] for line in f.split("\n"): if line == "don't()": enabled = False if line == "do()": enabled = True if enabled: for match in re.finditer(r"mul\((\d{1,3}),(\d{1,3})\)", line): muls.append(int(match.group(1)) * int(match.group(2))) pass pass print(sum(muls))
My first insinct was similar, add line breaks to the do and dont modifiers. But I got toa caught up thinking id have to keep track of the added characters, I wound up just abusing split()-
Really cool trick. I did a bunch of regex matching that I’m sure I won’t remember how it works few weeks from now, this is so much readable
Nice, sometimes a few extra linebreaks can do the trick…