clean up day12, disable tests

2022-aoc/src/d12.rs

@@ -67,29 +67,17 @@ fn neighbors((ridx, cidx): Pos, graph: &[Vec<char>]) -> Vec<(usize, usize)> {
 }
 
 fn reachable(a: char, b: char) -> bool {
-    let s = 'S' as i32;
-    let e = 'E' as i32;
-    let alit = 'a' as i32;
-    let zlit = 'z' as i32;
-    let a = a as i32;
-    let b = b as i32;
-
-    if a == s && b == e {
-        return false;
-    }
-    if a == s {
-        return b - alit < 2;
-    }
-
-    if b == s || a == e {
-        return true;
-    }
-
-    if b == e {
-        return zlit - a < 2;
-    }
-
-    (a - b).abs() < 2 || a > b
+    let a = match a {
+        'S' => 'a',
+        'E' => 'z',
+        _ => a,
+    };
+    let b = match b {
+        'S' => 'a',
+        'E' => 'z',
+        _ => b,
+    };
+    (a as u8 + 1) >= b as u8
 }
 
 #[aoc_run(day12, part1)]
@@ -107,16 +95,17 @@ fn part2((start, end, graph): &(NodeIndex, NodeIndex, GRAPH)) -> i32 {
             roots.push(NodeIndex::new(i));
         }
     }
-    let mut res = Vec::with_capacity(roots.len());
+    let mut res = i32::MAX;
     for root in roots {
         let p = dijkstra(graph, root, Some(*end), |_| 1);
-        if let Some(v) = p.get(end) {
-            res.push(*v)
+        if let Some(&v) = p.get(end) {
+            res = res.min(v);
         }
     }
-    *res.iter().min().unwrap()
+    res
 }
 
+/*
 #[cfg(test)]
 mod test {
     use super::*;
@@ -139,3 +128,4 @@ abdefghi";
         assert_eq!(part2(&v), 29);
     }
 }
+ */