Found a C per-char solution, that is, no lines, splitting, lookahead, etc. It wasn't even necessary to keep match lengths for the color names because they all have unique characters, e.g. 'b' only occurs in "blue" so then you can attribute the count to that color.

int main()
{
	int p1=0,p2=0, id=1,num=0, r=0,g=0,b=0, c;

	while ((c = getchar()) != EOF)
		if (c==',' || c==';' || c==':') num = 0; else
		if (c>='0' && c<='9') num = num*10 + c-'0'; else
		if (c=='d') r = MAX(r, num); else
		if (c=='g') g = MAX(g, num); else
		if (c=='b') b = MAX(b, num); else
		if (c=='\n') {
			p1 += (r<=12 && g<=13 && b<=14) * id;
			p2 += r*g*b;
			r=g=b=0; id++;
		}

	printf("%d %d\n", p1, p2);
	return 0;
}

Golfed:

c,p,P,i,n,r,g,b;main(){while(~
(c=getchar()))c==44|c==58|59==
c?n=0:c>47&c<58?n=n*10+c-48:98
==c?b=b>n?b:n:c=='d'?r=r>n?r:n
:c=='g'?g=g>n?g:n:10==c?p+=++i
*(r<13&g<14&b<15),P+=r*g*b,r=g
=b=0:0;printf("%d %d\n",p,P);}

My solutions in C: https://git.sr.ht/~aidenisik/aoc23/tree/master/item/day2

Most of this is just reading the data, surely there's a better way to do this lol.

Not too tricky today. Part 2 wasn't as big of a curveball as yesterday thankfully. I don't think it's the cleanest code I've ever written, but hey - the whole point of this is to get better at Rust, so I'll definitely be learning as I go, and coming back at the end to clean a lot of these up. I think for this one I'd like to look into a parsing crate like nom to clean up all the spliting and unwrapping in the two from() methods.

https://github.com/capitalpb/advent_of_code_2023/blob/main/src/solvers/day02.rs

#[derive(Debug)]
struct Hand {
    blue: usize,
    green: usize,
    red: usize,
}

impl Hand {
    fn from(input: &str) -> Hand {
        let mut hand = Hand {
            blue: 0,
            green: 0,
            red: 0,
        };

        for color in input.split(", ") {
            let color = color.split_once(' ').unwrap();
            match color.1 {
                "blue" => hand.blue = color.0.parse::().unwrap(),
                "green" => hand.green = color.0.parse::().unwrap(),
                "red" => hand.red = color.0.parse::().unwrap(),
                _ => unreachable!("malformed input"),
            }
        }

        hand
    }
}

#[derive(Debug)]
struct Game {
    id: usize,
    hands: Vec,
}

impl Game {
    fn from(input: &str) -> Game {
        let (id, hands) = input.split_once(": ").unwrap();
        let id = id.split_once(" ").unwrap().1.parse::().unwrap();
        let hands = hands.split("; ").map(Hand::from).collect();
        Game { id, hands }
    }
}

pub struct Day02;

impl Solver for Day02 {
    fn star_one(&self, input: &str) -> String {
        input
            .lines()
            .map(Game::from)
            .filter(|game| {
                game.hands
                    .iter()
                    .all(|hand| hand.blue <= 14 && hand.green <= 13 && hand.red <= 12)
            })
            .map(|game| game.id)
            .sum::()
            .to_string()
    }

    fn star_two(&self, input: &str) -> String {
        input
            .lines()
            .map(Game::from)
            .map(|game| {
                let max_blue = game.hands.iter().map(|hand| hand.blue).max().unwrap();
                let max_green = game.hands.iter().map(|hand| hand.green).max().unwrap();
                let max_red = game.hands.iter().map(|hand| hand.red).max().unwrap();

                max_blue * max_green * max_red
            })
            .sum::()
            .to_string()
    }
}

Python

Questions and feedback welcome!

import collections

from .solver import Solver

class Day02(Solver):
  def __init__(self):
    super().__init__(2)
    self.games = []

  def presolve(self, input: str):
    lines = input.rstrip().split('\n')
    for line in lines:
      draws = line.split(': ')[1].split('; ')
      draws = [draw.split(', ') for draw in draws]
      self.games.append(draws)

  def solve_first_star(self):
    game_id = 0
    total = 0
    for game in self.games:
      game_id += 1
      is_good = True
      for draw in game:
        for item in draw:
          count, colour = item.split(' ')
          if (colour == 'red' and int(count) > 12 or  # pylint: disable=too-many-boolean-expressions
                colour == 'blue' and int(count) > 14 or
                colour == 'green' and int(count) > 13):
            is_good = False
      if is_good:
        total += game_id
    return total

  def solve_second_star(self):
    total = 0
    for game in self.games:
      minimums = collections.defaultdict(lambda: 0)
      for draw in game:
        for item in draw:
          count, colour = item.split(' ')
          minimums[colour] = max(minimums[colour], int(count))
      power = minimums['red'] * minimums['blue'] * minimums['green']
      total += power
    return total

Ruby

https://github.com/snowe2010/advent-of-code/blob/master/ruby_aoc/2023/day02/day02.rb

Second part was soooo much easier today than yesterday. Helps I solved it exactly how he wanted you to solve it I think.

I'm going to work on some code golf now.

Golfed P2 down to 133 characters:

p g.map{_1.sub!(/.*:/,'')
m=Hash.new(0)
_1.split(?;){|r|r.split(?,){|a|b,c=a.split
m[c]=[m[c],b.to_i].max}}
m.values.reduce(&:*)}.sum

String parsing! Always fun in C!

https://github.com/sjmulder/aoc/blob/master/2023/c/day02.c

int main(int argc, char **argv)
{
	char ln[256], *sr,*srd,*s;
	int p1=0,p2=0, id, r,g,b;

	for (id=1; (sr = fgets(ln, sizeof(ln), stdin)); id++) {
		strsep(&sr, ":");
		r = g = b = 0;

		while ((srd = strsep(&sr, ";")))
		while ((s = strsep(&srd, ",")))
			if (strchr(s, 'd')) r = MAX(r, atoi(s)); else
			if (strchr(s, 'g')) g = MAX(g, atoi(s)); else
			if (strchr(s, 'b')) b = MAX(b, atoi(s));
	
		p1 += (r <= 12 && g <= 13 && b <= 14) * id;
		p2 += r * g * b;
	}

	printf("%d %d\n", p1, p2);
	return 0;
}

Python, interesting that the readMax function that I created on part 1 was also what I needed for part 2. https://github.com/massahud/advent-of-code-2023/blob/main/day02/day02.ipynb

Late as always, as I'm on UK time and can't work on these until late evening.

Part 01 and Part 02 in Rust 🦀 :

use std::{
    env, fs,
    io::{self, BufRead, BufReader},
};

#[derive(Debug)]
struct Sample {
    r: u32,
    g: u32,
    b: u32,
}

fn split_cube_set(set: &[&str], colour: &str) -> Option {
    match set.iter().find(|x| x.ends_with(colour)) {
        Some(item) => item
            .trim()
            .split(' ')
            .next()
            .expect("Found item is present")
            .parse::()
            .ok(),
        None => None,
    }
}

fn main() -> io::Result<()> {
    let args: Vec = env::args().collect();
    let filename = &args[1];
    let file = fs::File::open(filename)?;
    let reader = BufReader::new(file);
    let mut valid_game_ids_sum = 0;
    let mut game_power_sum = 0;
    let max_r = 12;
    let max_g = 13;
    let max_b = 14;
    for line_result in reader.lines() {
        let mut valid_game = true;
        let line = line_result.unwrap();
        let line_split: Vec<_> = line.split(':').collect();
        let game_id = line_split[0]
            .split(' ')
            .collect::>()
            .last()
            .expect("item exists")
            .parse::()
            .expect("is a number");
        let rest = line_split[1];
        let cube_sets = rest.split(';');
        let samples: Vec = cube_sets
            .map(|set| {
                let set_split: Vec<_> = set.split(',').collect();
                let r = split_cube_set(&set_split, "red").unwrap_or(0);
                let g = split_cube_set(&set_split, "green").unwrap_or(0);
                let b = split_cube_set(&set_split, "blue").unwrap_or(0);
                Sample { r, g, b }
            })
            .collect();
        let mut highest_r = 0;
        let mut highest_g = 0;
        let mut highest_b = 0;
        for sample in &samples {
            if !(sample.r <= max_r && sample.g <= max_g && sample.b <= max_b) {
                valid_game = false;
            }
            highest_r = u32::max(highest_r, sample.r);
            highest_g = u32::max(highest_g, sample.g);
            highest_b = u32::max(highest_b, sample.b);
        }
        if valid_game {
            valid_game_ids_sum += game_id;
        }
        game_power_sum += highest_r * highest_g * highest_b;
    }
    println!("Sum of game ids: {valid_game_ids_sum}");
    println!("Sum of game powers: {game_power_sum}");
    Ok(())
}

[LANGUAGE: C#]

Part 1:

var list = new List((await File.ReadAllLinesAsync(@".\Day 2\PuzzleInput.txt")));
int conter = 0;
foreach (var line in list)
{
    string[] split = line.Split(":");
    int game = Int32.Parse( split[0].Split(" ")[1]);
    string[] bagContents = split[1].Split(";");
    var max = new Dictionary() { { "red", 0 }, { "green", 0 }, { "blue", 0 } };
    foreach (var content in bagContents)
    {
        string pattern = @"(\d+) (\w+)";
        MatchCollection matches = Regex.Matches(content, pattern);

        foreach (Match match in matches)
        {
            int number = Int32.Parse(match.Groups[1].Value);
            string color = match.Groups[2].Value;
            max[color] = (max[color] >= number)? max[color] : number;
        }
    }
    conter += (max["red"] <= 12 && max["green"] <= 13 && max["blue"] <= 14) ? game : 0;

}
Console.WriteLine(conter);

Part 2:

var list = new List((await File.ReadAllLinesAsync(@".\Day 2\PuzzleInput.txt")));

int conter = 0;
foreach (var line in list)
{
    string[] split = line.Split(":");
    int game = Int32.Parse(split[0].Split(" ")[1]);
    string[] bagContents = split[1].Split(";");
        var max = new Dictionary();
    foreach (var content in bagContents)
    {
        string pattern = @"(\d+) (\w+)";

        MatchCollection matches = Regex.Matches(content, pattern);

        foreach (Match match in matches)
        {
            int number = Int32.Parse(match.Groups[1].Value);
            string color = match.Groups[2].Value;
            if (!max.ContainsKey(color))
                max[color] = number;
            else if(max[color] < number)
                max[color] = number;
        }
    }
    conter += max.Values.Aggregate(1, (total, value) => total *  value );

}
Console.WriteLine(conter);

Was pretty simple in Python with a regex to get the game number, and then the count of color. for part 2 instead of returning true/false whether the game is valid, you just max the count per color. No traps like in the first one, that I've seen, so it was surprisingly easy

def process_game(line: str):
    game_id = int(re.findall(r'game (\d+)*', line)[0])

    colon_idx = line.index(":")
    draws = line[colon_idx+1:].split(";")
    # print(draws)
    
    if is_game_valid(draws):
        # print("Game %d is possible"%game_id)
        return game_id
    return 0

            
def is_game_valid(draws: list):
    for draw in draws:
        red = get_nr_of_in_draw(draw, 'red')
        if red > MAX_RED:
            return False
        
        green = get_nr_of_in_draw(draw, 'green')
        if green > MAX_GREEN:
            return False
        
        blue = get_nr_of_in_draw(draw, 'blue')
        if blue > MAX_BLUE:
            return False    
    return True
        
            
def get_nr_of_in_draw(draw: str, color: str):
    if color in draw:
        nr = re.findall(r'(\d+) '+color, draw)
        return int(nr[0])
    return 0


# f = open("input.txt", "r")
f = open("input_real.txt", "r")
lines = f.readlines()
sum = 0
for line in lines:
    sum += process_game(line.strip().lower())
print("Answer: %d"%sum)

Did mine in Odin. Found this day's to be super easy, most of the challenge was just parsing.

package day2

import "core:fmt"
import "core:strings"
import "core:strconv"
import "core:unicode"

Round :: struct {
    red: int,
    green: int,
    blue: int,
}

parse_round :: proc(s: string) -> Round {
    ret: Round

    rest := s
    for {
        nextNumAt := strings.index_proc(rest, unicode.is_digit)
        if nextNumAt == -1 do break
        rest = rest[nextNumAt:]

        numlen: int
        num, ok := strconv.parse_int(rest, 10, &numlen)
        rest = rest[numlen+len(" "):]

        if rest[:3] == "red" {
            ret.red = num
        } else if rest[:4] == "blue" {
            ret.blue = num
        } else if rest[:5] == "green" {
            ret.green = num
        }
    }

    return ret
}

Game :: struct {
    id: int,
    rounds: [dynamic]Round,
}

parse_game :: proc(s: string) -> Game {
    ret: Game

    rest := s[len("Game "):]

    idOk: bool
    idLen: int
    ret.id, idOk = strconv.parse_int(rest, 10, &idLen)
    rest = rest[idLen+len(": "):]

    for len(rest) > 0 {
        endOfRound := strings.index_rune(rest, ';')
        if endOfRound == -1 do endOfRound = len(rest)

        append(&ret.rounds, parse_round(rest[:endOfRound]))
        rest = rest[min(endOfRound+1, len(rest)):]
    }

    return ret
}

is_game_possible :: proc(game: Game) -> bool {
    for round in game.rounds {
        if round.red   > 12 ||
           round.green > 13 ||
           round.blue  > 14 {
            return false
        }
    }
    return true
}

p1 :: proc(input: []string) {
    totalIds := 0

    for line in input {
        game := parse_game(line)
        defer delete(game.rounds)

        if is_game_possible(game) do totalIds += game.id
    }

    fmt.println(totalIds)
}

p2 :: proc(input: []string) {
    totalPower := 0

    for line in input {
        game := parse_game(line)
        defer delete(game.rounds)

        minRed   := 0
        minGreen := 0
        minBlue  := 0
        for round in game.rounds {
            minRed   = max(minRed  , round.red  )
            minGreen = max(minGreen, round.green)
            minBlue  = max(minBlue , round.blue )
        }

        totalPower += minRed * minGreen * minBlue
    }

    fmt.println(totalPower)
}

Getting my head around parsing tricks for python, maybe abusing dicts as a replacement for a types, but appears to be working: https://gist.github.com/purplemonkeymad/983eec7ff0629e8834163b17ec673958

Today in Zig

Spent most of the time running down annoying typos in the tokenizer.

I'm a bit late to the party for day 2. Here's my answer:

use std::rc::Rc;

use crate::utils::read_lines;

#[derive(Clone, Copy, PartialEq, Eq)]
enum Cube {
    Red(usize),
    Green(usize),
    Blue(usize),
}

#[derive(Clone, Copy, PartialEq, Eq)]
struct Bag {
    pub red: usize,
    pub green: usize,
    pub blue: usize,
}

fn parse_num<'a, I>(mut group: I) -> usize
where
    I: Iterator,
{
    group
        .next()
        .expect("Should be number")
        .parse::()
        .expect("Should be number")
}

fn process_lines() -> impl Iterator> {
    read_lines("src/day_2/input.txt")
        .expect("Could not read file")
        .map(|line| {
            let line = line.expect("Should be line");
            (&line[(line.find(':').unwrap() + 1)..])
                .split(';')
                .flat_map(|section| section.split(","))
                .map(|group| {
                    let mut group = group.trim().split(' ');

                    match group.next_back().expect("Should be color") {
                        "red" => Cube::Red(parse_num(group)),
                        "green" => Cube::Green(parse_num(group)),
                        "blue" => Cube::Blue(parse_num(group)),
                        c @ _ => panic!("Color {c} not recognized"),
                    }
                })
                .collect::>()
        })
        .into_iter()
}

pub fn solution_1() {
    let bag = Bag {
        red: 12,
        green: 13,
        blue: 14,
    };
    let sum: usize = process_lines()
        .enumerate()
        .map(|(i, line)| {
            let is_possible = line.iter().all(|cube| match cube {
                Cube::Red(c) => *c <= bag.red,
                Cube::Green(c) => *c <= bag.green,
                Cube::Blue(c) => *c <= bag.blue,
            });

            if is_possible {
                i + 1
            } else {
                0
            }
        })
        .sum();

    println!("{sum}");
}

pub fn solution_2() {
    let powersum: usize = process_lines()
        .map(|line| {
            let bag = line.iter().fold(
                Bag {
                    red: 0,
                    blue: 0,
                    green: 0,
                },
                |mut bag, cube| {
                    match *cube {
                        Cube::Red(n) => {
                            if n > bag.red {
                                bag.red = n;
                            }
                        }
                        Cube::Green(n) => {
                            if n > bag.green {
                                bag.green = n;
                            }
                        }
                        Cube::Blue(n) => {
                            if n > bag.blue {
                                bag.blue = n;
                            }
                        }
                    }

                    bag
                },
            );

            bag.red * bag.blue * bag.green
        })
        .sum();

    println!("{powersum}");
}

Factor on github (with comments and imports):

: known-color ( color-phrases regexp -- n )
  all-matching-subseqs [ 0 ] [
    [ split-words first string>number ] map-supremum
  ] if-empty
;

: line>known-rgb ( str -- game-id known-rgb )
  ": " split1 [ split-words last string>number ] dip
  R/ \d+ red/ R/ \d+ green/ R/ \d+ blue/
  [ known-color ] tri-curry@ tri 3array
;

: possible? ( known-rgb test-rgb -- ? )
  v<= [ ] all?
;

: part1 ( -- )
  "vocab:aoc-2023/day02/input.txt" utf8 file-lines
  [ line>known-rgb 2array ]
  [ last { 12 13 14 } possible? ] map-filter
  [ first ] map-sum .
;

: part2 ( -- )
  "vocab:aoc-2023/day02/input.txt" utf8 file-lines
  [ line>known-rgb nip product ] map-sum .
;