undo some of the excessive "cleaning"

1 files changed, 8 insertions, 2 deletions

diff --git a/utils.py b/utils.py
index 7aaaa61..2328cc2 100644
--- a/utils.py
+++ b/utils.py
@@ -38,9 +38,14 @@ def a_star(
         return ret
 
     open_heapq: list[tuple[float, int]] = [(h(start), intern(start))]
+    open_set: set[int] = {intern(start)}
     g_score: defaultdict[T, float] = defaultdict(lambda: float("inf"), [(start, 0)])
-    while open_heapq:
-        f, current = heappop(open_heapq)
+    while open_set:
+        while True:
+            f, current = heappop(open_heapq)
+            if current in open_set:
+                break
+        open_set.remove(current)
         current = itov[current]
         if callable(goal):
             if goal(current):
@@ -53,4 +58,5 @@ def a_star(
                 g_score[neighbour] = tentative_g
                 f_score = tentative_g + h(neighbour)
                 heappush(open_heapq, (f_score, intern(neighbour)))
+                open_set.add(intern(neighbour))
     return None