feat: Day 2

aoc_2025/src/day2.rs

@@ -0,0 +1,86 @@
+use crate::AoC;
+use winnow::{
+    Parser, Result,
+    ascii::digit1,
+    combinator::{separated, separated_pair},
+};
+
+type Parsed = Vec<(u64, u64)>;
+
+const AOC: AoC<Parsed> = AoC::new(parse, part1, part2);
+
+fn parse(input: String) -> Parsed {
+    let mut input: &str = input.as_str();
+    separated(1.., parse_range, ",")
+        .parse_next(&mut input)
+        .unwrap()
+}
+
+fn parse_range(input: &mut &str) -> Result<(u64, u64)> {
+    separated_pair(digit1.parse_to(), "-", digit1.parse_to()).parse_next(input)
+}
+
+fn part1(input: &Parsed) -> String {
+    let res = input
+        .iter()
+        .map(|(from, to)| {
+            (*from..=*to)
+                .filter(|i| {
+                    let n = (i.ilog10() + 1) >> 1;
+                    let p = 10u64.pow(n);
+                    i / p == i % p
+                })
+                .sum::<u64>()
+        })
+        .sum::<u64>();
+    format!("{res}")
+}
+
+fn part2(input: &Parsed) -> String {
+    let res = input
+        .iter()
+        .map(|(from, to)| {
+            (*from..=*to)
+                .filter(|i| {
+                    let n = (i.ilog10() + 1);
+                    (1..=(n >> 1)).filter(|p| n % p == 0).any(|p| {
+                        (1..(n / p))
+                            .all(|s| i % 10u64.pow(p) == (i / 10u64.pow(p * s)) % 10u64.pow(p))
+                    })
+                })
+                .sum::<u64>()
+        })
+        .sum::<u64>();
+    format!("{res}")
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn part1_test() {
+        AOC.assert1(
+            "11-22,95-115,998-1012,1188511880-1188511890,222220-222224,1698522-1698528,446443-446449,38593856-38593862,565653-565659,824824821-824824827,2121212118-2121212124",
+            "1227775554",
+        );
+    }
+
+    #[test]
+    fn part1_solve() {
+        AOC.assert1(include_str!("../input/day2.txt"), "12599655151");
+    }
+
+    #[test]
+    fn part2_test() {
+        AOC.assert2(
+            "11-22,95-115,998-1012,1188511880-1188511890,222220-222224,1698522-1698528,446443-446449,38593856-38593862,565653-565659,824824821-824824827,2121212118-2121212124",
+            "4174379265",
+        );
+    }
+
+    #[test]
+    fn part2_solve() {
+        AOC.assert2(include_str!("../input/day2.txt"), "20942028255");
+    }
+}

aoc_2025/src/lib.rs

@@ -1,7 +1,7 @@
 #![allow(dead_code)]
 #![allow(unused)]
 
-mod day1;
+mod day2;
 
 struct AoC<T> {
     parse: fn(String) -> T,