convert to aoc-runner and day1 solutions

src/day1.rs

@@ -0,0 +1,60 @@
+use aoc_runner_derive::{aoc, aoc_generator};
+use itertools::Itertools;
+use std::io::BufRead;
+
+#[aoc_generator(day1)]
+// Sum the calories of each elf's food items
+fn parse(input: &[u8]) -> Vec<u64> {
+    let mut result = Vec::new();
+    let mut cur_elf = 0u64;
+    for line in input.lines() {
+        if let Ok(calories) = line.unwrap().parse::<u64>() {
+            cur_elf += calories
+        } else {
+            result.push(cur_elf);
+            cur_elf = 0
+        }
+    }
+    result.push(cur_elf);
+    result
+}
+
+#[aoc(day1, part1)]
+fn part1(input: &Vec<u64>) -> u64 {
+    *input.iter().max().unwrap()
+}
+
+#[aoc(day1, part2)]
+fn part2(input: &Vec<u64>) -> u64 {
+    input.iter().sorted().rev().take(3).sum::<u64>()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const EXAMPLE: &[u8] = b"1000
+2000
+3000
+
+4000
+
+5000
+6000
+
+7000
+8000
+9000
+
+10000";
+
+    #[test]
+    fn part1_example() {
+        assert_eq!(part1(&parse(EXAMPLE)), 24000);
+    }
+
+    #[test]
+    fn part2_example() {
+        assert_eq!(part2(&parse(EXAMPLE)), 45000);
+    }
+}