Solutions for 2022, as well as 2015-2018 and 2019 up to day 11

2016/day03-squares_with_three_sides/Cargo.toml

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+[package]
+name = "day03-squares_with_three_sides"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

2016/day03-squares_with_three_sides/challenge.txt

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+\--- Day 3: Squares With Three Sides ---
+----------
+
+Now that you can think clearly, you move deeper into the labyrinth of hallways and office furniture that makes up this part of Easter Bunny HQ. This must be a graphic design department; the walls are covered in specifications for triangles.
+
+Or are they?
+
+The design document gives the side lengths of each triangle it describes, but... `5 10 25`? Some of these aren't triangles. You can't help but mark the impossible ones.
+
+In a valid triangle, the sum of any two sides must be larger than the remaining side. For example, the "triangle" given above is impossible, because `5 + 10` is not larger than `25`.
+
+In your puzzle input, *how many* of the listed triangles are *possible*?
+
+Your puzzle answer was `1050`.
+
+\--- Part Two ---
+----------
+
+Now that you've helpfully marked up their design documents, it occurs to you that triangles are specified in groups of three *vertically*. Each set of three numbers in a column specifies a triangle. Rows are unrelated.
+
+For example, given the following specification, numbers with the same hundreds digit would be part of the same triangle:
+
+```
+101 301 501
+102 302 502
+103 303 503
+201 401 601
+202 402 602
+203 403 603
+
+```
+
+In your puzzle input, and instead reading by columns, *how many* of the listed triangles are *possible*?
+
+Your puzzle answer was `1921`.
+
+Both parts of this puzzle are complete! They provide two gold stars: \*\*
+
+At this point, all that is left is for you to [admire your Advent calendar](/2016).
+
+If you still want to see it, you can [get your puzzle input](3/input).

2016/day03-squares_with_three_sides/src/lib.rs

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+pub fn run(input: &str) -> (usize, usize) {
+    let first = input.lines().filter(|t| check_trinangle(t)).count();
+    let collected_lines: Vec<_> = input.lines().map(|l| l.split_whitespace().collect::<Vec<_>>()).collect();
+    let second = collected_lines.chunks(3).map(|lines| {
+        (0..3).filter(|i| {
+            let (a, b, c): (usize, usize, usize) = ( lines[0][*i].parse().unwrap(), lines[1][*i].parse().unwrap(), lines[2][*i].parse().unwrap() );
+            let max = a.max(b).max(c);
+            a+b>max && b+c>max && a+c>max
+        }).count()
+    }).sum();
+    (first, second)
+}
+
+fn check_trinangle(line: &str) -> bool {
+    let components: Vec<_> = line.split_whitespace().collect();
+    assert_eq!(components.len(), 3);
+    let (a, b, c): (usize, usize, usize) = ( components[0].parse().unwrap(), components[1].parse().unwrap(), components[2].parse().unwrap() );
+    let max = a.max(b).max(c);
+    a+b>max && b+c>max && a+c>max
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::fs::read_to_string;
+
+    fn read_file(name: &str) -> String {
+        read_to_string(name).expect(&format!("Unable to read file: {}", name)[..])
+    }
+
+    #[test]
+    fn test_challenge() {
+        let challenge_input = read_file("tests/challenge_input");
+        assert_eq!(run(&challenge_input), (1050, 1921));
+    }
+}