solution: day 10 (ugly)

src/days.rs

@@ -7,7 +7,7 @@ pub mod d6;
 pub mod d7;
 pub mod d8;
 pub mod d9;
-// pub mod d10;
+pub mod d10;
 // pub mod d11;
 // pub mod d12;
 // pub mod d13;

src/days/d10.rs

@@ -0,0 +1,124 @@
+use crate::prelude::*;
+
+pub type I = (M<SS, Vec<u32>>, M<SS, (SS, SS)>);
+pub type O = SS;
+
+fn _parse (data: &'static str) -> I {
+    let mut initial: M<SS, Vec<u32>> = M::new();
+    let mut maps = M::new();
+
+    for line in data.lines() {
+        if let Some(sfx) = line.strip_prefix("value ") {
+            let (val, out) = sfx.split_once(" goes to bot ").map(|(v, b)| (v.parse().unwrap(), b)).unwrap();
+            initial.entry(out).or_default().push(val);
+        } else {
+            let line = line.trim_start_matches("bot ");
+            let (source, dests) = line.split_once(" gives low to ").unwrap();
+            let (l, h) = dests.split_once(" and high to ").unwrap();
+
+            let l = l.strip_prefix("bot ").unwrap_or(l);
+            let h = h.strip_prefix("bot ").unwrap_or(h);
+
+            maps.insert(source, (l, h));
+        }
+    }
+
+    (initial, maps)
+}
+
+#[allow(suspicious_double_ref_op)]
+fn _silver ((mut state, map): I) -> O {
+    let mut cur = state.iter().find(|e| e.1.len() == 2).unwrap().0.clone();
+
+    loop {
+        let chips = state.entry(cur).or_default();
+
+        let a = chips[0];
+        let b = chips[1];
+
+        chips.clear();
+
+        if (a == 17 && b == 61) || (b == 17 && a == 61) { return cur; }
+
+        let (low, high) = map.get(cur).unwrap();
+
+        let l_entry = state.entry(low).or_default();
+        l_entry.push(if a > b { b } else { a });
+        let l_len = l_entry.len();
+
+        let h_entry = state.entry(high).or_default();
+        h_entry.push(if a > b { a } else { b });
+        let h_len = h_entry.len();
+
+
+        cur = if l_len == 2 {
+            low
+        } else if h_len == 2 {
+            high
+        } else {
+            state.iter().find(|e| e.1.len() == 2).unwrap().0
+        }
+    }
+}
+
+#[allow(suspicious_double_ref_op)]
+fn _gold ((mut state, map): I) -> u32 {
+    let mut cur = state.iter().find(|e| e.1.len() == 2).unwrap().0.clone();
+
+    loop {
+        let chips = state.entry(cur).or_default();
+
+        let a = chips[0];
+        let b = chips[1];
+
+        chips.clear();
+
+        let (low, high) = map.get(cur).unwrap();
+
+        let l_entry = state.entry(low).or_default();
+        l_entry.push(if a > b { b } else { a });
+        let l_len = l_entry.len();
+
+        let h_entry = state.entry(high).or_default();
+        h_entry.push(if a > b { a } else { b });
+        let h_len = h_entry.len();
+
+        if let Some(a) = state.get("output 0") && let Some(b) = state.get("output 1") && let Some(c) = state.get("output 2") {
+            return a[0] * b[0] * c[0]
+        }
+
+        cur = if l_len == 2 {
+            low
+        } else if h_len == 2 {
+            high
+        } else {
+            state.iter().find(|e| e.1.len() == 2).unwrap().0
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    fn read () -> I {
+        let data = inc!(10);
+        _parse(data)
+    }
+
+    #[test]
+    fn silver () {
+        let data = read();
+        let ans = _silver(data);
+
+        assert_eq!(ans, s!(116))
+    }
+
+    #[test]
+    fn gold () {
+        let data = read();
+        let ans = _gold(data);
+
+        assert_eq!(ans, 23903)
+    }
+}