solution: day3

src/bin/03.rs

@@ -0,0 +1,62 @@
+use itertools::Itertools;
+
+pub fn part_one(input: &str) -> Option<usize> {
+    Some(
+        input
+            .lines()
+            .map(|x| {
+                x.split_whitespace()
+                    .map(|x| x.parse::<usize>().unwrap())
+                    .collect_vec()
+            })
+            .map(|x| [x[0], x[1], x[2]])
+            .filter(|&[a, b, c]| a + b > c && a + c > b && c + b > a)
+            .count(),
+    )
+}
+pub fn part_two(input: &str) -> Option<usize> {
+    let mut triangles = Vec::new();
+
+    for chunk in input
+        .lines()
+        .map(|x| {
+            x.split_whitespace()
+                .map(|x| x.parse::<usize>().unwrap())
+                .collect_vec()
+        })
+        .chunks(3)
+        .into_iter()
+    {
+        let (l1, l2, l3) = chunk.collect_tuple().unwrap();
+
+        for i in 0..=2 {
+            triangles.push([l1[i], l2[i], l3[i]]);
+        }
+    }
+
+    Some(
+        triangles
+            .into_iter()
+            .filter(|&[a, b, c]| a + b > c && a + c > b && c + b > a)
+            .count(),
+    )
+}
+fn main() {
+    let input = &aoc::read_file("inputs", 3);
+    aoc::solve!(1, part_one, input);
+    aoc::solve!(2, part_two, input);
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_part_one() {
+        let input = aoc::read_file("examples", 3);
+        assert_eq!(part_one(&input), Some(2));
+    }
+    #[test]
+    fn test_part_two() {
+        let input = aoc::read_file("examples", 3);
+        assert_eq!(part_two(&input), Some(1));
+    }
+}

src/examples/03.txt

@@ -0,0 +1,3 @@
+5 10 25
+2  2  3
+6 13 15