Cruise ships are great for this

Excel

Pt1 - Its a solution, but the column width on Numbers prevents a full solution

https://docs.google.com/spreadsheets/d/e/2PACX-1vTzFApVAk9k5Q4EQhozST1HftYLgVzApgxjQx7MAl5AAE5eWEvrQnDQWmdj7J2Hyw/pub?output=ods

If I get p2 working, I'll post a new link. Dont think i will have much luck though.

Because I wasn't aware of them, thanks!

Yeah, Im hoping it picks up. No mazes yet :(

I used to sleep with a hammer under my bed. Since he started this medication, I can sleep more easily, and I don’t need to sleep with the hammer anymore.

That is such a sad quote. That they ever thought that was normal or okay.

Ulua probably has a single character that rotates the input -90 degrees...

Rust

Pt1 easy, pt2 cry

edit: Updated with more iterring :)

    #[test]
    fn test_y2025_day6_part1() {
        let input = include_str!("../../input/2025/day_6.txt");
        let lines = input.lines().collect::<Vec<&str>>();
        let nr = lines[0..4]
            .iter()
            .map(|l| {
                l.split_whitespace()
                    .map(|s| s.parse::<usize>().unwrap())
                    .collect::<Vec<usize>>()
            })
            .collect::<Vec<Vec<usize>>>();
        let operations = lines[4].split_whitespace().collect::<Vec<&str>>();

        let total = operations
            .iter()
            .enumerate()
            .map(|(i, op)| match *op {
                "*" => [0, 1, 2, 3].iter().map(|j| nr[*j][i]).product::<usize>(),
                "+" => [0, 1, 2, 3].iter().map(|j| nr[*j][i]).sum::<usize>(),
                _ => panic!("Unknown operation {}", op),
            })
            .sum::<usize>();
        assert_eq!(4412382293768, total);
        println!("Total: {}", total);
    }

    #[test]
    fn test_y2025_day6_part2() {
        let input = std::fs::read_to_string("input/2025/day_6.txt").unwrap();
        let lines = input
            .lines()
            .map(|s| s.chars().collect::<Vec<char>>())
            .collect::<Vec<Vec<char>>>();
        let mut i = lines[0].len();

        let mut numbers = vec![];
        let mut total = 0;
        while i > 0 {
            i -= 1;
            let number = [0, 1, 2, 3]
                .iter()
                .filter_map(|j| lines[*j][i].to_digit(10))
                .fold(0, |acc, x| acc * 10 + x);
            if number == 0 {
                continue;
            }
            numbers.push(number as usize);
            match lines[4][i] {
                '*' => {
                    total += numbers.iter().product::<usize>();
                    numbers.clear();
                }
                '+' => {
                    total += numbers.iter().sum::<usize>();
                    numbers.clear();
                }
                ' ' => {}
                _ => panic!("Unknown operation {}", lines[4][i]),
            }
        }
        assert_eq!(7858808482092, total);
        println!("Total: {}", total);
    }

Day 4 - https://youtube.com/shorts/8O9ypsGgApA

Yup, in the pinned post: https://programming.dev/post/6631465 :)

Rust

   #[test]
    fn test_y2025_day5_part2() {
        let input = std::fs::read_to_string("input/2025/day_5.txt").unwrap();
        let (fresh, _) = input.split_once("\n\n").unwrap();
        let mut fresh = fresh
            .lines()
            .map(|l| {
                let (p1, p2) = l.split_once("-").unwrap();
                (p1.parse::<usize>().unwrap(), p2.parse::<usize>().unwrap())
            })
            .collect::<Vec<(usize, usize)>>();

        fresh.sort_by_key(|a| a.0);

        let mut non_overlapping = vec![*fresh.first().unwrap()];

        for range in fresh[1..].iter() {
            let last = *non_overlapping.last().unwrap();
            if range.0 > last.1 {
                // println!("Non overlapping: {range:?} -> {last:?}");
                non_overlapping.push((range.0, range.1));
                continue;
            }
            if range.0 <= last.1 && range.1 > last.1 {
                // println!("Overlapping: {range:?} -> {last:?}");
                let new_last = (last.0, range.1);
                non_overlapping.pop();
                non_overlapping.push(new_last);
                continue;
            }
            // println!("{range:?} is entirely within {last:?}");
        }

        let mut count = 0;
        for r in &non_overlapping {
            count += r.1 - r.0 + 1;
        }
        assert_eq!(count, 352556672963116);
        println!("{}", count);
    }

Took me way longer than it should have to work out pt2, got tripped up by a < instead of <=.

1 is impossible. You cannot screen every message sent, even screening every post would be a full time 24/7 job (3x full time moderators working in shifts).

The big platforms will run it through a blackbox content moderator system, and lobby to keep fines minimal. Lemmy would be screwed.