2023: day01: part 1

aoc2023/src/day01.rs

@@ -0,0 +1,50 @@
+use std::fmt::Write;
+
+use anyhow::Result;
+
+const INPUT: &str = include_str!("../input/day01.txt");
+
+pub fn run() -> Result<String> {
+    let mut res = String::with_capacity(128);
+
+    writeln!(res, "part 1: {}", part1(INPUT)?)?;
+    writeln!(res, "part 2: {}", part2(INPUT)?)?;
+
+    Ok(res)
+}
+
+fn part1(input: &str) -> Result<u64> {
+    let digit_list = input
+        .lines()
+        .map(|s| s.chars().filter(char::is_ascii_digit).collect::<String>());
+
+    Ok(digit_list
+        .map(|digits| {
+            let first = digits.chars().next().unwrap().to_digit(10).unwrap() as u64;
+            let last = digits.chars().last().unwrap().to_digit(10).unwrap() as u64;
+
+            first * 10 + last
+        })
+        .sum())
+}
+
+fn part2(input: &str) -> Result<u64> {
+    todo!()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const PROVIDED: &str = include_str!("../input/day01_provided.txt");
+
+    #[test]
+    fn part1_provided() {
+        assert_eq!(part1(PROVIDED).unwrap(), 142);
+    }
+
+    #[test]
+    fn part1_real() {
+        assert_eq!(part1(INPUT).unwrap(), 54697);
+    }
+}

aoc2023/src/lib.rs

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+pub mod day01;

aoc2023/src/main.rs

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+use anyhow::Result;
+
+use aoc::DayFunc;
+
+use aoc2023::day01;
+
+fn main() -> Result<()> {
+    let days: &[DayFunc] = &[day01::run];
+
+    aoc::run(days)
+}