checkpoint

day06/src/main.rs

@@ -117,7 +117,7 @@ impl Board {
         parse(input).unwrap()
     }
 
-    fn step(&mut self) -> Option<Loc> {
+    fn step(&mut self) -> Option<(Loc, Dir)> {
         let (loc, dir) = &mut self.guard;
         *self
             .cells
@@ -133,12 +133,12 @@ impl Board {
             match next_cell {
                 Cell::Obstacle => {
                     *dir = dir.rot();
-                    Some(*loc)
+                    Some((*loc, *dir))
                 }
                 Cell::Empty | Cell::Visited => {
                     *next_cell = Cell::Guard(*dir);
                     *loc = nloc;
-                    Some(nloc)
+                    Some((nloc, *dir))
                 }
                 _ => unreachable!(),
             }
@@ -150,7 +150,7 @@ impl Board {
     fn run(&mut self) -> usize {
         let mut locs = HashSet::new();
         locs.insert(self.guard.0);
-        while let Some(loc) = self.step() {
+        while let Some(loc) = self.step().map(|l| l.0) {
             locs.insert(loc);
         }
         locs.len()
@@ -234,5 +234,7 @@ mod test {
     }
 
     #[test]
-    fn p2() {}
+    fn p2() {
+        assert_eq!(6, pt2(INPUT));
+    }
 }