2022 Day 1

2022/src/bin/day01.rs

@@ -0,0 +1,53 @@
+const INPUT: &str = include_str!("../../input/day01.txt");
+
+fn main() {
+    println!("{}", part1(INPUT).unwrap());
+    println!("{}", part2(INPUT).unwrap());
+}
+
+#[derive(Debug, Clone, Default)]
+struct Elf {
+    fruits: Vec<u32>,
+}
+
+impl Elf {
+    fn total(&self) -> u32 {
+        self.fruits.iter().sum()
+    }
+}
+
+fn part1(input: &str) -> anyhow::Result<u32> {
+    let mut elves: Vec<Elf> = vec![];
+
+    for section in input.split("\n\n") {
+        let mut elf = Elf::default();
+
+        for fruit in section.split('\n').filter(|line| !line.is_empty()) {
+            let cals: u32 = fruit.parse()?;
+            elf.fruits.push(cals);
+        }
+
+        elves.push(elf);
+    }
+
+    let most_food = elves.iter().cloned().max_by_key(Elf::total).unwrap();
+    Ok(most_food.total())
+}
+
+fn part2(input: &str) -> anyhow::Result<u32> {
+    let mut elves: Vec<Elf> = vec![];
+
+    for section in input.split("\n\n") {
+        let mut elf = Elf::default();
+
+        for fruit in section.split('\n').filter(|line| !line.is_empty()) {
+            let cals: u32 = fruit.parse()?;
+            elf.fruits.push(cals);
+        }
+
+        elves.push(elf);
+    }
+
+    elves[..].sort_by_key(|e| std::cmp::Reverse(e.total()));
+    Ok(elves[0..3].iter().map(Elf::total).sum())
+}