Day 6 Part 2 Slow

Author: philip-ly

2024/day_06/Python/guards.py

@@ -33,28 +33,48 @@ def out_of_bounds(area, cursor) -> bool:
     )
 
 
-def count_paces(area_str: str) -> int:
-    area_list_of_lists = [list(line) for line in area_str.splitlines()[1:]]
-    area = np.array(area_list_of_lists)
-    area = np.pad(area,1, "constant",constant_values='_')
-
-    (cursor,) = np.argwhere(area == "^")
+def has_loop(area) -> int:
     direction = np.array([-1, 0])
 
     total_visited = 0
     newly_visited = True
+    visited_set = set()
+    (cursor,) = np.argwhere(area == "^")
+
 
-    while not area[tuple(cursor)] == "_":
+
+    while not (area[tuple(cursor)] == "_" or (tuple(cursor),tuple(direction)) in visited_set):
+        visited_set.add((tuple(cursor),tuple(direction)))
         total_visited += newly_visited
         cursor, direction, newly_visited = walk(area, cursor, direction)
 
-    return total_visited
+    return (tuple(cursor),tuple(direction)) in visited_set
+
+def iterate_obstacles(area_str: str):
+    area_list_of_lists = [list(line) for line in area_str.splitlines()[1:]]
+    area = np.array(area_list_of_lists)
+    area_padded = np.pad(area,1, "constant",constant_values='_')
+    loops = 0
+
+    for x_pos in range(1, area_padded.shape[0]-1):
+        for y_pos in range(1, area_padded.shape[1]-1):
+            area_copy = area_padded.copy()
+            # print(x_pos, y_pos)
+            if area_padded[(x_pos, y_pos)] == "^":
+                print("HELP ME")
+            else:
+                area_copy[(x_pos,y_pos)] = "#"
+                if has_loop(area_copy):
+                    loops+=1
+        print(x_pos)
+
+    return loops
 
 
 def main():
     with open("input","r") as f:
         data = f.read()
-    print(count_paces(data))
+    print(iterate_obstacles(data))
 
 
 if __name__ == "__main__":

2024/day_06/Python/test_guards.py

@@ -1,5 +1,4 @@
-from guards import count_paces
-
+from guards import iterate_obstacles
 
 INPUT = """
 ....#.....
@@ -16,4 +15,4 @@
 
 
 def test_guards():
-    assert count_paces(INPUT) == 41
+    assert iterate_obstacles(INPUT) == 6