Day1

1 files changed, 106 insertions, 0 deletions

diff --git a/day1/src/main.rs b/day1/src/main.rs
new file mode 100644
index 0000000..fd78563
--- /dev/null
+++ b/day1/src/main.rs
@@ -0,0 +1,106 @@
+struct Day1 {}
+
+impl Day1 {
+    fn part_n(&self, input: BufReader<Box<dyn Read>>) -> (Vec<u32>, Vec<u32>) {
+        let mut a: Vec<u32> = vec![];
+        let mut b: Vec<u32> = vec![];
+
+        for line in self.read_lines(input) {
+            let mut s = line.split(' ');
+
+            loop {
+                let ia = s.next().unwrap();
+
+                let num = match ia.parse::<u32>() {
+                    Ok(num) => num,
+                    Err(_) => continue,
+                };
+
+                a.push(num);
+                break;
+            }
+
+            loop {
+                let ib = s.next_back().unwrap();
+
+                let num = match ib.parse::<u32>() {
+                    Ok(num) => num,
+                    Err(_) => continue,
+                };
+
+                b.push(num);
+                break;
+            }
+        }
+
+        (a, b)
+    }
+}
+
+impl Day for Day1 {
+    fn example_input(&self) -> &'static str {
+        r#"
+        3   4
+        4   3
+        2   5
+        1   3
+        3   9
+        3   3
+        "#.trim()
+    }
+
+    fn example_result_part_1(&self) -> &'static str {
+        "11"
+    }
+
+    fn example_result_part_2(&self) -> &'static str {
+        "31"
+    }
+
+    fn part_1(&self, input: BufReader<Box<dyn Read>>) -> String {
+        let (mut a, mut b) = self.part_n(input);
+
+        a.sort();
+        b.sort();
+
+        let mut distances: Vec<u32> = vec![];
+        for (ia, ib) in a.iter().zip(b) {
+            if *ia > ib {
+                distances.push(ia - ib);
+            } else {
+                distances.push(ib - ia);
+            }
+        }
+
+         format!("{}", (distances.iter().sum::<u32>()))
+    }
+
+    fn part_2(&self, input: BufReader<Box<dyn Read>>) -> String {
+        let (a, b) = self.part_n(input);
+
+        let mut scores: Vec<u32> = vec![];
+        for item in a {
+            let count = b.iter().filter(|&&i| i == item).count();
+            scores.push(item * count as u32);
+        }
+
+        format!("{}", (scores.iter().sum::<u32>()))
+    }
+}
+
+use aoc;
+use std::io::{BufReader, Read};
+use aoc::Day;
+
+fn main() {
+    aoc::main(&Day1 {});
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_day1() {
+        aoc::test_day(&Day1 {});
+    }
+}