[rs] Solve 2022_01

rs/src/d01.rs

@@ -1,4 +1,31 @@
 pub fn solve(input: String) -> anyhow::Result<()> {
-    println!("TODO!");
+    let mut elves = vec![];
+    let mut elf = vec![];
+    for line in input.lines() {
+        if let Ok(number) = line.trim().parse::<u32>() {
+            elf.push(number);
+        } else {
+            elves.push(elf);
+            elf = vec![];
+        }
+    }
+    if !elf.is_empty() {
+        elves.push(elf);
+    }
+
+    let mut elves = elves
+        .into_iter()
+        .map(|e| e.into_iter().sum())
+        .collect::<Vec<u32>>();
+    elves.sort_unstable();
+
+    // Part 1
+    let top = elves.last().unwrap();
+    println!("Part 1: {top}");
+
+    // Part 2
+    let top_three = elves.iter().rev().take(3).sum::<u32>();
+    println!("Part 2: {top_three}");
+
     Ok(())
 }