clean up a*

1 files changed, 7 insertions, 18 deletions

diff --git a/utils.py b/utils.py
index afdd191..7aaaa61 100644
--- a/utils.py
+++ b/utils.py
@@ -37,31 +37,20 @@ def a_star(
             i += 1
         return ret
 
-    open_set: set[T] = {start}
-    open_heapq: list[tuple[float, int]] = [(0, intern(start))]
-    came_from: dict[T, T] = dict()
-    g_score: defaultdict[T, float] = defaultdict(lambda: float("inf"))
-    g_score[start] = 0
-    f_score: dict[T, float] = dict()
-    f_score[start] = h(start)
-    while open_set:
-        while True:
-            f, current = heappop(open_heapq)
-            current = itov[current]
-            if current in open_set:
-                break
+    open_heapq: list[tuple[float, int]] = [(h(start), intern(start))]
+    g_score: defaultdict[T, float] = defaultdict(lambda: float("inf"), [(start, 0)])
+    while open_heapq:
+        f, current = heappop(open_heapq)
+        current = itov[current]
         if callable(goal):
             if goal(current):
                 return f
         elif current == goal:
             return f
-        open_set.remove(current)
         for neighbour in neighbours(current):
             tentative_g = g_score[current] + d(current, neighbour)
             if tentative_g < g_score[neighbour]:
-                came_from[neighbour] = current
                 g_score[neighbour] = tentative_g
-                f_score[neighbour] = tentative_g + h(neighbour)
-                open_set.add(neighbour)
-                heappush(open_heapq, (f_score[neighbour], intern(neighbour)))
+                f_score = tentative_g + h(neighbour)
+                heappush(open_heapq, (f_score, intern(neighbour)))
     return None